No high level player is hitting a forehand with a passive arm.
I've become suspicious of instruction based on feeling, because how each of us interprets what he does can be quite different. Something that feels effortless today could be the result of a lot of effort based practice yesterday.
I believe that video of actual movement patterns is the best way to improve. If you get a certain feeling when moving correctly you can use that as feedback, but only if the video confirms the movement.