Hmm. So far, I have been allowing it, and it has not caused any problems. Of course, it has gone into the calculations for my skill-based magic system, which is balanced at the top end with a min/max 18 Intelligence/Unearthly Ancestry/Skill Focus: Spellcraft build. What do you see as the problems with allowing Skill Focus/Affinity with magical skills?
I think I am confusing EoMR with the Mythic Earth teaser, because a glance back at the EoMR rules shows that you can indeed use Skill Focus with magical skills. Never mind, then.
