Hm. I think that such a strategy might fare well in cases where you're trying to catch errors in your thinking itself, but I usually find myself simply lacking brainpower -- I probably make more errors as well, but the primary cost is that I don't work as fast, learn as fast etc. This sort of thing seems harder to eliminate.
I'm also thinking that the only similar hindrance that one might encounter if they were under (time?) pressure would be tiredness -- hunger/thirst/mild pain are solved in the short term by just adding a few things to your bag.
Systema (Let Every Breath-- sorry, no time for links) trains mental focus while in oxygen debt.
When I originally wrote "When to scream 'Error!'", I was mainly thinking of bad patterns of thought or bad problem-solving strategies as being the source of the error. Since then, I've come to realize that my own most common source of stupidity is because I've neglected some comfort. I may be hungry without consciously paying attention to it, dehydrated because I've been living on coffee for too long, or simply have a headache and need to take an Ibuprofen -- as a result, I don't think well, get irritated at the fact that I'm not thinking well, and generally begin a death spiral if I don't realize why.
In hindsight, it feels obvious that I should take care of the physiological needs that I can because they're likely preventing me from thinking straight. However, I've failed to do this on numerous occasions and so thought it worth mentioning.
In summary: Whenever you're screaming "Error", I suggest you stop and figure out whether you're hungry, thirsty, tired, or hurting before trying to find a problem in your thinking itself, especially if you're not usually good at noticing such things.