I don't know if the helps but here is my experience:
I have always tried to walk upriver when bank fishing, especially on smaller rivers or when the water is ultra low. This gives me the chance to slowly look over the holding water from below the fish. So I can see them before they see me if they are laying in close to the bank or in the shallow water. But if i do not see any fish in the shallow water or close to bank I proceed to the top of the hole and work my way downriver. as to present my offering in front of the fish. In these conditions it seems best to walk up river and then survey the water and fish the holding water from top to bottom.
I can give you a tip on the sandshrimp: you either need to use just the tail and rig it they way bob shows in his tips section (best with rags or aeroflies). If you want to use the whole shrimp (best plain or with just a corkie or similar bobber) the best thing to do is thread the tail up the leader and have the hook push through the hard part of the head so the point is sticking out. Also, I have found that with whole shrimp a smaller hook is better as the big hooks tear the shrimp up. An oldtimer showed me this trick on my home river, he said the shrimp has to be laid out flat as to look natural as it drifts down, not all balled up. One other note, if you want to fish shrimp whole make sure they are fresh, otherwise they will "explode" when you go to cast.

I hope this helps you.

good luck