BPM sync / Master Sync

Can you just sync bpm without the slip of the master affecting the other track?

I have found sometimes after I have dropped a tune and I want to make a small adjustment to the one that is on the way out, I need to be careful to make sure the master has swapped over, otherwise it slips the one that is dominant. I can change it over, but then sometimes Ill cut the main tune out for a couple of beats, then it swaps back over without me knowing.

Can I just have the BPM always set to the same, but still have flexibility to slip either deck as I wish without having to think about which is master, or do I just need to leave it off altogether?