If thats what happened to you, probably yes..
I enhance Yakov with another Yakov (both melee, lvl 1 2* card) and get 348exp with Yakov ended up being lvl4.
If I enhance Yakov with, lets say Claire (melee 1* lvl1), I get 149exp and Yakov lv2.
Both scenarios done under maxed Blessing of the Valkyrie.