I think that no matter what the goal multijoint movements are the best!! I have all my clients do them, and of course so I follow my own advice.. They burn more cals, they are harder, and of course they are fuctional... Once I took all the fluff mvments out of leg traininng i took my physique up a notch, (or atleast I think)....My name is Squat Ass, not ham curl ass..haha... Its kinda like all the fat chicks on the good girl bad girl machine.. They need to get there fat asses off that dumb machine and do some squats and lunges..
Sometimes single jt mvments are good for some rehab stuff, but if you can train hard then you should. (I do think that adding in some single jt stuff closer to show time or when dieting is a good idea b.c there is less fat to cover up those big muscles)
Squat Ass