The main issue with FoL is that if you are main healing, it doesn't heal for enough to keep up with the incoming flow of damage (at least in my experience). While HL can, its slow cast really hurts...hence Light's Grace making HL feasible to cast without giving your tank a heart attack.
Granted, I've never main healed in BC (was Holy pre-BC), and back before BC hit most Pallies just spammed FoL due to the long cast time of HL. I just know that the Holy Pallies I run with tend to use HL quite a bit, but then again we're only in Kara/Gruul's - not anywhere near as progressed/geared as Lore's guild.
_________________
