Time makes fools of us all!
I was fermenting a 1.25 gallon pale ale for my single-hop lineup (Chinook this time), in a 2.5-gallon glass jar with a crappy thin metal screw top. Using WY1764 that was repitched from a Simcoe beer that really came out great in the same vessel. I did not pitch onto the cake, but... honestly, I can't remember what I did! Maybe I have some notes in Beersmith.
Anyway, two weeks and a few days later, I decided it was time to bottle. This was probably the first batch ever that I didn't test it for gravity at all, so I never opened the jar to smell or taste it. It spent 2 days in my bathtub under a paper bag to block out light, then I moved it to my fermentation fridge that had been full of bottles from another brew. I also left it out in my garage for a few days after I moved it to make room for 3 new 1-gallon batches. I thought I'd bottle that day but didn't.
And so, bottling time! Removed the lid, took a whiff... Nail polish remover and nothing else. Took a taste... Sour as all get-out, just pure vinegar. I'm thinking acetobacter!
So, I'm now evaluating all the things I've been doing wrong: Milling in my kitchen, lax sanitization, open-ish fermentation... Time to give my gear a deep clean and tighten up my brew day routines!