I think its possible to use AT without sucking the life out of the performance..
It's just a matter of how you use it.

I rarely use it as a plugin on a whole track (unless intentionally wanting that sound or working with a really poor singer).
Rather using it to 'touch up' a phrase here or there can easily be pulled off without needing a tin ear.
Don't rely on it, but don't be afraid of it.
It's a tool best used in sparse moderation most of the time.

Even then, a good AT can be used pretty transparently if set up correctly; ie it doesn't touch the sound unless it gets off by over 'X' amount. Then you can adjust how fast and how accurately it does kick in. These are the tell tale points.
Problem is, many just pick a key and the preset settings and let 'er go.
Highlighting a phrase and correcting a note or two (judiciously) can be done pretty effectively in most cases, if you want to put in the time to get it right.

Make your sound your own!
.. I do not work here, but the benefits are still awesome