Bard/druid/healer don't focus enough on combat to learn the techniques. There are other edges that do this aren't there? "Those with sufficient martial training" type thing.

Rangers have wilderness fam which trumps it, so they don't need it/want it.

Hence, warrior-only.

Outlander will obviously get more use out of it, but no reason Battle and Nexus won't. Battle has wilderness right near their cabal and Nexus fights all over the place theoretically.

Heralds? Who cares? ;). They can use it in exploring.