Dr. Darden,
what is your opinion of these machines, i.e.best for bicep development
and was Arthur wrong about performing bicep curls with the elbows elevated above the shoulders as in the nautilus compound machine
i have a choice between the preacher curl and the hammer bicep curl, your opinion
Others opinion are welcome also
The best biceps and triceps exercises for me are full range chins and partial dips.
I believe doing both machines, in an alternating manner, would be better than focusing on just one.
I was actually thinking the same…you taught me well, 
I never tried a bicep machine I liked … none felt too good on my elbows.
My best feel on biceps come from low incline hammer curls followed by one dumbbell curl - the dumbbell is on end and your hands under the top end, palms up. You can’t go all the way down to a straight arm or you’ll lose the dumbbell but following the hammer curls, it doesn’t matter. Two sets of each and that’s it.
I do these following back where biceps got worked hard with rows and pulldowns.
This!!! Chins are probably what’s made the biggest difference in my biceps. Be careful of course and control the descent, no need for bicep tears.
