JohnScott, after some testing in the doctors small tank I think at times the wire on top will cause the fly to ride upside down. If the fly is under good line tension the fly tracks true, but in stiller waters or when on a slack line or dead drifted it may tumble and/or possibly ride upside down. Remember though the real bugs are getting knocked all over the place in the current as well and the dead and crippled bugs are drifting helplessly along in all kinds of positions. I've caught a lot of fish on this fly but again I always try and fish it with a tight line. These flies are used to simulate the caddis flies hatching from the bottom and shooting to the waters surface.....
So, like any other fly you tie, tie it the way you like. I think I will change the pattern and eliminate the wire on top altogether just to be on the safe side.... good observation JohnScott, thanks for bringing it up.
Steven, the wire head alone acts just like a bead head on any fly you tie... I tie these without WH's or BH's too...