“at the expense of overall utility” is unnecessary for the “short-sighted” bit: that is implied by the phrase. Short-sighted-ness is a well known character flaw.
And your version is still bad. Over-optimising at the expense of overall utility is hard to parse. You’re missing “one aspect”. You shouldn’t over-optimise one aspect at the expense of overall utility.
“Do not over-optimise one aspect at the expense of overall utility”
Good phrasing.
but which is better . . . .
You should not over-optimize or be short-sighted at the expense of overall utility.
OR
You should not be short-sighted or over-optimize at the expense of overall utility.
“at the expense of overall utility” applies to both halves of the statement
Is it still just as bad? Or was the initial comment a bit hasty and unwarranted in that respect?
“at the expense of overall utility” is unnecessary for the “short-sighted” bit: that is implied by the phrase. Short-sighted-ness is a well known character flaw.
And your version is still bad. Over-optimising at the expense of overall utility is hard to parse. You’re missing “one aspect”. You shouldn’t over-optimise one aspect at the expense of overall utility.