Wrists should be unhinging into and through contact.
"Bat drag" is a condition where the rear elbow gets significantly ahead of the hands and puts the hitter in a position of dragging the bat along its length. This is an extreme example...
EricF, what you describe here is often a 'result' of what folks term 'bat drag'. From this point onwards the barrel is flung/flailed to impact. It's actually a powerful type whipping action.
If you don't agree with this pic being a good illustration of "bat drag", maybe you could help NVF by posting a better one.
Looking closer at the the pic I posted, I'm not sure I agree that this position would result in a "powerful type whipping action" with the wrists already unhinged that far at this point in the swing.
EricF, the picture you show is the 'result' of the barrel essentially being already dragged. It's more an indicator ... and not necessarily a full proof indicator. Bat drag in this swing could have been detected much earlier ... which is where the correction needs to be ... much earlier.
Ummmm...okay. I'm not quite sure what you're getting at, FFS. Do you think that the pic I posted is a poor illustration of bat drag for the purposes of answering NVF's original question? Per his own description, NVF is a noob and requested a simple explanation that was easy to digest. I made an attempt to help. Like I said, if you think there's a better picture to use to illustrate bat drag, go for it. If you have a better description than the one I offered, have at it. If you have some additional tips on how to detect it and correct it, I'm sure someone will appreciate it.
Had they actually identified what ‘bat drag’ was, and then attacked that, then they would have likely been much more successful … IMO anyway.