Based on mine blooming so late in the season, I wouldn't. I don't cut mine back and they bloom fine. Why do you think this one will not bloom?

I thought it would act like mums: cut/pinch in early summer for bushiness and to delay bloom. Reportedly, if mums are cut back too late they might not have time to set buds and bloom before a killing frost. There are a lot of different mums out there so that may be an inaccurate generalization.

I was going to hack off some divisions from edges and figured I´d cut it back several inches to make it easier. Also assumed some stems would break or get bent so it might be better to trim everything.

In general, I dont think it looks graceful as a 4 foot shrub. I also wonder if it fall under itś own weight when it flowers or whether a good wind or heavy rains will cause it to flop, never to rise again.

Trying to stake at this point in the season would not be a rewarding chore. More reading is order. And less worrying....cut or not....wait and see what happens. It/s all information!