Semi-Hydro question for a phal that is about to be transplanted

[Ray]

I usually reduce the light, but keep them especially warm - especially in the root zone - by setting the pots on a heat mat.

The theory being that warmth accelerates the plant's metabolism, and focusing it on the root zone, while reducing the light input to the leaves, favors root growth over leaf growth. I know the warm-root-zone part is true; the low light part might be BS.

On the other hand, reducing the light prevents overheating the leaf tissue, but that certainly shouldn't be an issue for normal phalaenopsis light levels.