Last year I bought Silverettas to access climbs in Quebec, seemed like a killer solution to avoiding carrying two pair of boots or slowshoeing 16 miles into Parc Jacques Cartier.
I used them once on a short approach to make sure they didn't fall apart (they did a bit, but probably because my DIN is too low/I am terrified of them breaking my ankle- anyhow they go back together easily).
Then I brought them to PJC and skiied 16 miles on them and they absolutely destroyed my heels- biggest blisters of my life. Imagine your entire heel was a blister.
Obviously my ice boots don't articulate like my AT boots.
What is the solution? I tried looser, I tried tighter, neither seemed to help.