JetBlue TrueBlue - Why 6:50 block time for BOS-OAK?

Does anyone know why JetBlue uses a 6h50m block time for BOS-OAK? AA and UA use approximately 6h30m block times for BOS-SFO, and SFO gets much more backed up than OAK ever does. Yes, 20 minutes is actually a big deal.

Are they trying to improve their on-time arrival ratings by padding the schedule even worse than the legacy airlines do?

I didn't check other routes, but it could be interesting to compare JetBlue's block times on routes to those of legacies.

Does anyone know why JetBlue uses a 6h50m block time for BOS-OAK? AA and UA use approximately 6h30m block times for BOS-SFO, and SFO gets much more backed up than OAK ever does. Yes, 20 minutes is actually a big deal.

Are they trying to improve their on-time arrival ratings by padding the schedule even worse than the legacy airlines do?

I didn't check other routes, but it could be interesting to compare JetBlue's block times on routes to those of legacies.

If I had to guess, I would have to say that it is because of the aircraft. The 767/757 is much more powerful then the A320.

Hasn't jetBlue been having problems with the range of the A320 in certain conditions? Maybe the extra 20 minutes comes from having to fly at a slightly slower, more fuel efficient airspeed?