The real danger in MUCH hotter loads is premature unlocking of the action and a case blow out. I've fired +P in 1911s, but I always go with a more appropriate recoil spring rate. Wilsons, Wolff, and others offer spring kits for the 1911 in various weights up to heavy enough for the .45 Super. I used to also use a recoil buffer, a little plastic thing from Wilsons that slid over the spring guide and cushioned the shock of the slide to frame. Hot loads in my AMT Hardballer started showing a little flair on the slide where it contacts the frame, the reason I installed the recoil buffers. They don't last forever and a session with +P stuff even with the 22 lb spring installed would smash one flat, but they were cheap and good insurance.
I kept +P stuff to a bare minimum in my 1911s because of the wear I saw on the slide, flaring where it contacts the frame, in just a few hundred rounds. Even with an appropriately heavy spring and the recoil buffers, I did not feel the 1911 was really up to the task of shooting much +P. They need to be tested in the gun if you're going to carry them, then used very sparingly IMHO in a 1911. My Ruger P90 will eat 'em all day long and twice on Sunday, but it's a much stronger built gun with a heavier slide (more slide weight = less recoil velocity) and I use heavy springs in it, too. I don't feel that an unaltered 1911 should be fired with +P at all.
BUT, that's just my humble opinion and not anything based on other than my own experience and personal paranoias. This is not specific to the PT1911, but ANY 1911. They were NOT originally designed for such pressures after all. The design is nearly 100 years old, from a time when smokeless powder was quite new and exotic, let alone the concept of +P pressures.