Cheat reps are fantastic because they at least put some strain on your body when you would have otherwise completely stopped your set. If your form is good and you decide that it's impossible to keep lifting without "cheating" at the end of your set, then by all means go for it. My original post was really for people who fly into the gym and begin showing off because they can bench/squat/curl so much when their form is just generally really bad.
And yeah I definitely agree and ultimately it comes down to what your body best responds to.
And yeah I definitely agree and ultimately it comes down to what your body best responds to.