I just happen to have grown up in East Dennis! There is pretty excellent fishing all up and down. I've had most of my luck in between Corporation and sesuit harbor. There is structure all around there. Most of my fishing had been drifting eels from a boat about 20 yrds off shore....I've never caught anything off the sesuit jetty but skates.......that was in my early days.
The jetty at Corp is supposed to have Tautog behind it. In fact the huge rock is aptly named "tautog rock"
anyway enough of this calaver..........
in short.....you are fishing in a great area. keep at it!
No two tides are the same