how do you fish creek or river channel drop offs   Do you place the boat in the channel and cast to the shore running the bait from shallow to deep or place the boat close to the shore and cast into the channel running from deep to shallow  

Great question!

I usually do both.  If you work it from deep to shallow with no success, try it shallow to deep.  Another tactic is to work your bait along the ledge working it shallow to deep or vice versa.  You also cover more water doing that.

It doesn't matter as long as you are on or very near the drop. The Tennessee River is maintained for year around commercial barge traffic. The channel is defined by permanent buoys. I fish the imaginary line between the buoys extensively and catch smallmouth on either side of the break.

Again as mentioned one of the ways that's work best for me is paralleling the ledge. Fish it at several depths for the fish may be suspended at different intervals along the ledge!