If you do get a blister and want to continue to rock on, here's the bomber treatment. Use either tincture of benzione or a product called Kanka for canker sores. This will hurt like HELL but seal the offending blister right away. Then tape it with cloth tape and with rounded edges so it doesn't get caught on your sock.
I had 2 seasons of relentless blisters. I found the right boots and got them sporadically. Then I switched socks. I dumped the liner and went to Dahlgren's - they did the trick. Hard to find but worth it.