Using wood or azek drip cap on a window or door head always becomes a problem for me when used in conjunction with cedar shingles. The lip on the back is too short and in the past I have always bent a drip cap which is a pain because you have to bend it back to the wall right over the lip so you can get the shingle and the undercoarse over it without bulging out. I have also cut the lip off and ran a wider metal drip on top of it. So I was thinking what if I just put sort of a z flashing over the lip and up the wall like a counterflashing and not covered the top of dripcap at all. I never liked the way the metal looked hanging over the side anyway, unless it was copper. Water problem?