Alas, that ballast is a light one, so there will less wing loading than
with a non-fluorescent light bulb.

However, I do find the fluorscent ones perfect for a 0-.5 kt max climb
rate day as they suck the optium amount of dark out of such light
soaring conditions.

See the article by Dick Johnson in Soaring, the chapter in Derek
Piggott's Understading Gliding, and the powerpoint link at Tom Knauff's
web page.