I was scared when I had to cut back my 12 ft plumeria early this past summer. It simply got too tall to handle. Plus the Riviera Rainbow had giant 18" leaves to boot making it very top heavy. It had bloomed once for the first time. But if I let it grow one more season, I knew I would have trouble getting it into the greenhouse.
I cut it down to 3 ft tall, and handed out generous cuttings to 3 people. I was so scared! But everyone here babied me through it. I over-worried when the 4" diameter stump rotted at the top. I doused it in peroxide and put Saran Wrap over it to protect it from the rain. Oh! How I worried!! That tree is now 6 feet tall again with 4 branches. It hasn't bloomed this year. But I bet next year it will surprise me.