Begining of season, I checked, and chain was barely showing wear. 2-3 months later and oops! at 1/16th and rollers are kinda loose. Need to step up my chain lubrication, clearly, as I doubt I have much more than 1kmiles on this chain. Anyhow, since this is the second chain I have worn out on this bike, I looked at the cassette, figuring I'd have more wear on the hill climbing gears--wrong. The gears I run in the flats may be worse: on the edge of the tooth where the roller would ride while pedaling hard, on the edge of it, I can easily catch a fingernail. As if the tooth was being hammered flat by the chain roller. I'm guessing, time for replacement?

Bike is a Trek Pilot 1.2, 9 speed setup, SRAM PC-951 chain (first chain was Shimano whatever). Cassette is whatever 12-25 that came with the bike. I've thought about stepping down to a 12-23 (not sure if an 11 would fit, nor my actual need for an 11) or maybe even 12-21, so it'd be a great time to try that idea out; but figured I'd ask before I assumed my cassette to be on its way out.

Thanks.