Hope you've gotten since your post, what worked ?
The "quick, severe violence" tactic worked for me when I got my doors stuck using '49 strikers with '52 doors. They felt too solidly stuck, so I was skeptical it would work.
I got inside, had a helper hold the outside handle unlatched, reared back and gave the door a mighty kick with my size 11 Sketchers, and to my surprise it popped open.
