Stumbled across this article: 7 Gym Exercises You Need to Avoid Agree or disagree? (obviously first 2 are no brainers)
some agrees, some disagrees, some are it depends on the technique and purpose of the exercise. I think will done correctly--incline sit-ups are as good as anything--but you have to do them with a great deal of control--we all learned to do sit-ups in PE class, ie, see how many you can do in two minutes, etc. and that can lead to problems. I like upright rows but with a much wider and thumbless grib and then only pulled to the mid-chest height or performed with dumbells. Leg Press--not nearly as good as squats, but I would not say its something to be competely avoided. Back Extension/Hyper-extension, I disagree, but I most people in metro gyms do it incorrectly Ab twist, agree, esp, on a machine
What I find interesting is they knock sit ups but advocate crunches, and I have to think done with good form (not leaning forward) sit ups are a better exercise all around than crunches. Not that I have anything to back that up...
The smith machine is a *very* useful piece of equipment, and has it's place in my heart.... .... for helping me hang off the bar when putting on my briefs and squat/deadlift suit.