Luckykathryn,
I presume by trying to 'feather' the prop during your quick circuit you mean coarsening the pitch (singles don't feather, thats the domain of twins and then only to prevent windmilling when the engine is shut down in flight).
Aerobatic props fail in coarse position if all pressure drops off, non-aero props go to fine. Feather is as coarse as it is possible to go!
What aircraft was it you were flying? If your prop was a 'fail fine' type its interesting that the rpm dropped!
The prop cycling pre take-off is not strictly to get the oil pressure to the prop but to check the function of the CSU and prop and get warm oil through the system and into the prop.
Glad you made it back to terra firma though!