Those darn creaks. Easy fix (this time)
I share so that others can learn from it. I had one of those dreaded creaks. It creaked in unison with my cadence. First thoughts - bottom bracket. Removed bb and regreased threads - re-assembled. Creak still there. Disassemble and grease pedals - same creak. Creak would be most noticeable on hard pulls, sprints and climbs.
Solution (in this case). The quick release wasn't tight enough allowing the wheel to move slightly in the drops. I just gave the QR a half turn tighter and the creak went away.
First thing I check next time
1970 Raleigh Tourist, 1972 Raleigh Sports, 1984 Miele Road Bike SS, 1985 Bianchi Nuovo Alloro, Cannondale F400, Opus Avro 29er, Jamis Sonik, Blue CXC, Bianchi San Jose, Cervelo SL-SLC, Cervelo S3 Di2 and a wife that loves me!