i would have to agree... i've had 3 rings and have never had a band. we've been married for 8 years now.I think it's trending towards one ring frmo the beginning, a nice setting w/ the solitaire as opposed to an e-ring plus a band.
That what we did 9 yrs ago and I'm actually going back and redoing it now. Now I want a solitaire on a plain band and want to add a diamond etenrity band to it.
My jeweler says she sells more one pieces than wedding sets now.
So my answer is, never, it wouldn't occur to me to not wear my e-ring.