[oconnor0]

I think one of the issues here is what compiler optimizations encompass. In a language like C or C++, you may be able to write optimal algorithms but end up with poor performance because of memory access. An unoptimized compile puts almost everything on the stack - a = b + c involves two loads, one add, and one store in an unoptimized compile. All of that extra memory access is going to kill performance; even if you have optimal data structures and algorithms.

I see "optimizations are bad/unnecessary/problematic/whatever" in my job writing a compiler. The underlying issue is almost never "I don't want optimizations" - even when someone thinks that's what they want; it's "I don't want optimizations that produce unexpected behavior".