Can they put another 1-point mastery into tier 2 on the Defense tree?

I just noticed that you literally cannot get to tier 3 in the Defense tree without taking either Block or Tough Skin.

Not that Block is a bad mastery by any means, it's just that you're forced to take it if you're not jungling and want 9 points in Defense.

Not that I know what a good 1-pointer would be for tier 2 offhand, though. I was thinking -2 minion damage on melee champs/-1 for ranged, but I'm not sure if that would be too much.