Is it rude to NOT tell your race when you choose Random?
People often make estimations based on what they would do. 'Fairness' is considered virtuous and a society that didn't would be eating away at itself.
Naturally, it's in the best interest of the larger 'body' of experience that is a society to advocate for 'virtues'. All virtues that I can think of share a common foundation in Empathy.
While I would argue that everyone has or acts virtous under different circumstances even if some do so against their nature, it is clear that some people in the eyes of a society are inherently more virtuous than others. And when people take accounting of their perceived virtues they feel empowered by societal norms in requesting equitability.
Also because of societal norms (it's good to talk about good but not so much bad) we often forget that we are all a bag of "good and bad" in different areas and self-perception of our virtues can often inflated or simply adjusted to what you think is the societal norm, especially in situations that you don't need to solve for yourself; such as playing Random on a regular basis, which most people just don't do by choice - they can, however, 'imagine' what they think they would do if they did.
So, playing Random would be one of those situations; your opponent doesn't play random, but he can simply ask "what would I do if I did?" and assign himself the virtuous route through a process that would often look like; (''I would say my race, virtue; fairness'') because it's either true that they would or it's just easiest / most convenient; That person, then, could think or claim it's rude (not to say your race) by assessing that the action falls below the societal line or their own standards and expectations of fairness and equitability.
Of course a range of possibilities exists so, for example, a 'more selfish' person could also think they understand the societal norm, while not thinking that they would tell their race and still look to take advantage by asking you to tell them your race, but that person would be less likely to comment on the rudeness aspect.
More often than not it will be the person who feels or thinks that they hold the moral high ground that demands/advocates for fairness from that podium.
The advantages of playing random are much more palpable than the disadvantages, because when removing the intangibles -or- difficult to quantify aspects that come along with human limitations, and, looking at the situation 'objectively' (post-removal); Random players play knowing the opponent's race, their opponents don't. The advantages are glaring for anyone that's ever played SC2, BW or WC3, because you usually start playing the game knowing your opponent's race and your first few steps while in the dark are geared to account for commonalities accordingly. On paper, that nets the randoming player a clear advantage.
Another advantage of playing random on the realm of [difficult to quantify] is that the experience of playing multiple races will open your eyes to certain weaknesses and strenghts relative to the other races' capabilities at a given point in the game allowing for more informed and thus better decision making and gameplay in turn; but people won't bitch about that because it's either not a present thought or it's easier to avoid the realm of [difficult to quantify] where, upon entry, it'd be silly not to account for the much larger disadvantages in turn.
I think that most things pertaining human limitations would fall heavily under the realm of difficult to quantify, but as much as our limitations vary in different areas, there is much common grounds from where to draw conclusions that are, like the realm of [difficult to quantify], not objective or true -enough- for everyone to feel at ease. These reasonings should and still do hold meaning, but I think that most of us are wired to repel uncertainty and so less tangible truths can easily be ignored as a result.
So if the advantages of playing random so heavily outweighted the opposite, why aren't ANY pros random?
I start with the question because while the reasons are a little more obscure (difficult to quantify), empirical evidence would clearly suggest that it is a pretty freaking big disadvantage to play Random at the highest level.
I think that this is all in great part because when you introduce human limitations to the equation the advantages that seem apparent are eclipsed by [time] and storage space to iterate and create processes in 3 wildly different directions that in-themselves require multiple branches of thought turned to action via your fingers (to a lesser scale within each sub-bracket).
Both Time and Memory (concious or subconcious) through iteration; account for cleaner, more refined processes in specific situations and for speed as you develop 'muscle memory' for said specific thoughts and/or processes.
A simple example is - most people reading this probably make probes drones and scvs without thinking about the key, and they do so at a very fast rate, because everyone has done that many times! - You then don't need to think "What key do I press to make drones" muscle memory takes care of all that to where your thoughts and hands are sync'd and if you think or your body knows to make workers at -X- junction, then you just do, and you do it very quickly, perhaps not significantly slower than Serral would, the more times you repeat the process the less you require concious thought and that in turn means that you can occupy your concious space with other thoughts and ideas, and you can build layers on top of layers and become nearly automated.
I can play StarCraft 2 without putting almost any thought into it or while thinking about other things and my body will just default to keep moving; things that I unconciously register would probably still trigger responses requiring minimum thought because it is the thoughts and understandings prior that are stored and that you build on top of and solve for, that is your muscle memory. Aided by active thoughts, interest and undivided attention, I will (of course) account for more variables and play better.
On "Autopilot", if I see shades of DTs and have a lair, I won't have to think much if at all for my hands to reach for the closest overlord and make an overseer, still when the thought is absent, I own the process; because in the past I have to have 'solved for it' and the thought "what can I do to solve the invisibility problem given my current tools" and the actions to validate the answers have both made enough 'passes' to be mostly automated, my body can then accept "DT=Overseer, if you can", that action will automate particuarly easily because there are not many exceptions to that rule and the less adjusting necessary, more common the process will be, like making your first few workers.
Then could come a situation where I find myself with banelings only to defend DTs, and the answer may not be so much automated because the situation will be less common. How many banelings do I need exactly to kill a DT? Do I hide them up my ramp to increase chances of hitting the DT if it's headed that way? Can the DT outrun my banes? How large is the AOE of banes? Did he get blink for his DTs? XD, these are all questions that may be fresher in my head and could occupy my concious space now, but that doesn't mean that I can't solve for each of them and have this specific process/problem be close to automated in time, even if it was full of Ifs and Buts.
So, while a person that mains 1 race uses 100% of their time and storage space allocated to StarCraft into that race, a player that plays random divides that time and memory in 3 and even though there is some overlap between the races, the thoughts and mechanical processes required for each are very different and thus also very demanding, enough so - that there are no pros willing to play random and rarely, if ever, Random players at the top of the ladder - despite the advantages that seem more palpable and despite every tournament ever allowing for the choice.
Of course, a non-random player could elect to play random at a given point in time and have a 1 in 3 chance to aquire an advantage at the expense of the 2 in 3 chance of a significant disadvantage given the few paragraphs above. It's not an invalid strategy if the disparity between players is large enough and aknowledged by the randoming player, but it never really sees any use and in the vast majority of cases it would be difficult to make an argument for it being the best course of action.
To conclude, a person who thinks it's rude to not tell your race probably hasn't thought through the limitations that you grapple with in order to play random at the level that you do and they may think (or act, or both) as though as if they have a moral high ground based on what they think is the virtuous way to go about things or what they think they would do in your shoes; most likely, in an atempt to speak on behalf of 'fairness' and while ignoring the intricacies and detriments of choosing random that while less obvious, are empirically very difficult to refute.
So I say go Random away, and don't tell no sh*t.