Up on the plate today: the importance of thinking, problem reduction, and generalisation, as illustrated through tactical examples. Case in point: it really bugs me when people that oughta know better write stuff that looks like
if (a == true) if (b == true) return false else if (b == false) return true end else if (a == false) if (b == true) return true else if (b == false) return false end end
Up front, don't laugh. I see crap like this all the time.
For those that may not see it, this is exactly equivalent to "a XOR b", and so could be equally expressed as
return a ^ b
Or, if your language of choice doesn't have XOR:
return a != b
I'm gonna go out on a limb and suggest that that code should never have been written. Any developer worth their salt should have seen that reduction right off the bat.
To paraphrase the always insightful Ezra Zygmuntowicz, "No code is better than no code". I'm hereby christening this phrase as "Ezra's Law", and will publicly state that anyone I find not following it in our committed code will be flogged, or at least made to buy me a beer.
(Note: feel free to substitute [ 'faster' | 'more correct' | 'more maintainable' | 'clearer' ] for 'better' )