That is not true, and I am not saying that it isn't workable. I am saying that it matters, and denying that it matters is nonsense.
This is fact. You admitted that it matters, and it doesn't just matter to huge honking engines. Like most things there are tolerances. So you can be within the tolerance with a match book, but you will not be working at optimum spec for your engine. So to say that it doesn't matter is wrong. Plain and simple. To say you don't care would be a more honest statement.
I for one have witnessed fouled plugs because of to little or to much of a gap. So if you are using tops matches you might be to wide, and if you are using Prince Albert roll up papers you might be to thin. Might as well do it right, and understand why you should be doing it right in the first place.