Are you sure this was an adult peregrine falcon, birdnut? It almost sounds like the actions of a juvenile just learning to fly. Could it be that Cowboy & Joli might have offspring? Do the adults actually wingersize? I thought they just up and take off.
Definitely not a juvenile - the Radisson chicks are our oldest chicks and they haven't fledged yet. And juveniles from outside the province would not be independent enough or strong enough to get up to Winnipeg to hang out on the Buhler Building - not that they could, Cowboy is very territorial and the fact that he is hanging out in the area means that he has not intention of relinquishing his spot to anyone.
To answer your question about whether an adult wingercizes, the answer is yes but it usually is something else that is making them do that, for example, when they come in with prey if it is too large or they don't have a good grip on it or they are landing against a cross-wind, they can look like they are wingercizing. After preening, particularly after it rains, you will see adults "dance" like the chicks, particularly if its hot and humid. And although it doesn't apply here, when peregrines play in ponds/puddles you can see them do it then as well. If it was Cowboy, and given how territorial he can be, particularly in the face of crows/ravens in his territory, he could have been blowing off steam or ensuring they know he's around. Because he and Joli are so close to the Radisson, they are a particularly quiet pair, so sometimes we have seen him be more physical because he can't be as vocal as perhaps he would like.
Considering that he kept going back to the same places, I think it is safe to rule out a hot roof scenario (though I do like the image of a peregrine on a hot tin roof
). From what I have observed of Cowboy over the last three years, I would suspect (because of course I didn't see it) that he was being territorial in response to something on the roof/building. Not people because at 5pm, staff aren't working on roof. However, the crows across the street should have chicks fledging and I would guess that Cowboy was reacting to a fledgling on the roof or on one of the front balconies. He stashes food on the signs so it could have been raiding his caches or perhaps he was trying to prevent someone from even thinking of raiding his cache. And he's been terrorizing crows whenever he sees/finds them since he turned up in 2011 ...
Good report Birdnut