Learning to use light armour

Is the skill "Learning to use light armour" helpful if i'm planning to use heavy armour later in the game? i don't want to waste any more LPs on things like this after learning the not-so-useful prospecting..

No, it's bugged, so it doesn't even work. Avoid it.

Prospecting is IMHO very useful, both for a few quests (gold and ore spring to mind), and for the moneymaking bastard sword recipe (among the best swords in the game if you make it yourself, and you can make it fairly early on, but it needs iron).

yes, because of the bugged skills (e.g. poisoned arrows et. al.) the tech-tree has become a sleuth's challenge and i'm kind of apprehensive of installing a patch midway in the game.. and also prospecting did come in handy for the quest where Nemrok needed 50 gold nuggets.. thanks to both of you..