Duerkey, I too was skeptical until I saw a DIY fixture on a smaller tank. The intensity of the light, the look and penetration was rather impressive. Thereafter I started to take LED's a little more seriously.
I would still love to follow a thread, where a reefer has been using LED's for quite some time & has some extensive before & after pics of SPS growth & clam support.
I am questioning the following though:
-LED's reducing algae growth. Sounds like a portion of the spectrum might be missing or too low. Corals would instinctively respond to this by extending themselves as much as they possibly can, in order to increase surface area and extract as much as possible. Coral extension might be misinterpreted as rapid growth.
This is something that I have observed with PC lights as well over the years. Acclimate the same corals to T5 lights & the corals don't extend as much, since there is no need to. Giving one the impression that T5's are not as affective. One would get more algae growth with the T5's as well, proof of their effectiveness.