I'd say source bless applies universally within your attack range, but yes it doesn't really pose a challenge to a distance based hit chance.
If I remember correctly you could do two movements for one AP in D:OS if the individual movements were small enough (I know I've had moves that cost 0 AP after my previous action was a movement. This was most apparent on characters with high movement.
All that being said your still going to have a relatively binary hit chance for melee weapons (limit to how far your sword reaches) so you would still have the potential issue of being just out of range of an attack and need to spend an AP repositioning.
