I recently read some tips on correcting an over-carbonated batch of bottled beer, tried a few, and thought I'd pass on the method that worked the best:
1. Refrigerate the beer to near-freezing
2. Uncap* the bottles just enough to continually let CO2
escape, keep refrigerated
3. Keep refrigerated for a week, remove, recap with your bottle capper
I tested this with a batch which was so over-carbonated, a 12oz bottle would fill a 1-gallon jug with pure foam and, when the foam condensed back into beer, it was ruined because the sediment at the bottom of the bottles had converted to foam as well, pretty much ruining the taste of the beer. (I didn't try re-crashing it via refrigeration, I instead started trying uncapping methods.) I found that when the beer is near-freezing, it releases carbonation slowly enough that the bottles didn't gush. I also found that it took EIGHT days until recapping left the bottles with normal carbonation.
If this helps even 1 person, we win.
* Careful to not bend the caps. I found an opener with a blade-shaped opener-lip worked best; do NOT use an old "church key" opener as it bends the edges of the cap