I have one major swing problem (not to mention all the small ones) that I can't figure out how to solve. When I am using a sand or lob wedge on a less than full shot I will about half the time shank the living daylights out of it. I have tried to swing more upright assuming that I was getting to flat trying to ease up on the swing and for a while it will be ok. Then, you guessed it it will come back. Always at the most inopportune time. And once it happens once I defy anyone not to think about it every time you get another half shot. Every so often I will even do it on a full swing with the sand and lob wedges from the turf. I NEVER do it from the sand on on a true flop shot. And I never have the problem with the gap wedge or any other iron!! Please give me some suggestions to try. This costs me sometimes 3 shots per round. even once cost me a berth in the club championship finals. HELP!!

Other than "Its in my head" any mechanical suggestions?