It's going to be interesting to see how it turns out. Genentech has already made a good return on lucentis, its recent run rate is >$800M. If it turns out the two drugs are similar in efficacy, I won't feel bad for dna. If lucentis is truly better then it will be a nice vindication for dna.
As far as powering, if genentech is saying you need a massive trial to detect differences that doesn't indicate they expect a large one. (would be nice to know how big a trial is planned so we can compare it to regn vegf trap vs lucentis for example).