Can a Paladin take and use Magical Knack, specifically if multi-classing with a non-spellcasting class?
I can't see any reason that would prevent it. It seems to be exactly what the trait was created for.
-S
I dont see why a paladin couldn't single class and use it... It states as long as your cl doesn't exceed your hd it's all good. Paladins cl is character level -3 at 4th, so with magical knack it would instead be -1 effectively. Get an orange ion stone and its equal to paladin level(for purposes of duration,feats etc. etc.). With that said it would work multiclassing as well..
I can't see any reason that would prevent it. It seems to be exactly what the trait was created for.
-S
As a 'Magic' Trait, I wasn't sure if it applied to Divine classes or spells. Definitely seems to be one of the most potent traits.