I would like to echo adirondack. I have had great success during caddis hatches by imparting a little movement onto my fly. When the fish break the surface by their whole body length, I think it is b/c they get a lot of speed chasing an emerger that is headed to the surface. I have dead drifted an EHC through a bunch of feeding fish and had it ignored, only to be slammed the minute I put some movement on it, either as adirondack suggested by letting it get wet and then pulling it up or by letting the fly swing at the end of the drift.
Life is hard. But it's a lot harder if you're stupid.