So I decided to take advantage of the friends and family XP bonus. I set up my second toon as a Paladin healer. I'm using 18 keys set up to match up to the 18 macro keys on a G15. Anyway, all of my beneficial spells (Heals, buffs, purify, etc..) I've set up with the following style macro:

/cast [target=player, modifier:shift] Blessing of Might; [target=focus] Blessing of Might

When I click on the macro with the mouse, it casts it on my focus as expected. When I shift+click it with the mouse, it casts it on my paladin, as expected. I've bound all the keys to F1-F12. When I press any of the F keys, the spell casts on my focus as I would expect it to, however, if I hold down the shift key and then press the F key, it does not cast on my paladin, or at all for that matter.

What am I doing wrong?