Yesterday I had the opportunity to perform Bach's "Ich will nur dir zu Ehren leben" from the Christmas Oratorio in Florida State's bi-weekly vocal seminar. It was my first time performing Bach in public, and I have to admit I was quite nervous. I am used to believing that in my fach I wasn't able to move my voice at those kinds of speeds. But now that I have pulled it off successfully, and seen what working on this piece did for the rest of my technique, I have decided I have to explore Bach further.
It appears that there is some truth to the idea that if you can sing Mozart and Bach, you can sing anything. I would encourage all "bigger" voices to look at ways to make your sound more flexible. I for one am tired of listening to heavier Verdi and Wagner being sung by voices that have vibratos wider than a mack-truck. One of my favorite recordings is Ben Heppner singing Idomeneo, flying through the coloratura. He is probably the most important American Heldentenor around, and yet listening to him sing Wagner is a delight because his voice still has such vibrancy.
So, though I spent most of my career thinking that Bach simply wasn't for me, I have changed my tune - literally :).