Denver,
I can relate. When I was younger, prior to bad hips, I was a mogul nut; either competing or teaching in the bumps most of the winter. When my hip got really bad, I had to restrict myself to softer rounder bumps, and stay out of the hacked up ones.
I got back into teaching full time (8 hours, seven days a week) at 6.5 months after my resurfacing, mostly high level skiing. I did warn my students that I would be avoiding nasty bumps for that first season. This turned out to be smart, because my hip did not really feel ready for much impact those first couple of months. I was skiing bottomless powder and crud my first day back, and within a few weeks was skiing very aggressively on the groomed, carving trenches at speed. By the end of that first season, I was back to skiing some black diamond bump runs, but I made a point of avoiding icy bumps or jagged lines.
I think that your docs advice was spot on; groomers are all good, powder and crud are good as long as there are no hidden surprises like rocks or stumps that could damage to a new hip (this risk is why I did not go heli-skiing that first year), and bumps as long as they are soft and round (or at least can be skied that way). I think that hitting hard zipper lines at speed during the first year would be a mistake. Dr. Gross's advice was to start skiing gradually at six months, and no bumps or black diamonds for a year. Last I heard, Mr McMinn was still saying no skiing at all for one year.
Hopefully it will not happen to you, but after skiing for over 50 years, my first turn on my new hip was a disaster. A week before the lifts opened, I had hiked about 1000 feet up the mountain to give my hip a test run. Stepped into my skis, started my first turn on the new hip, and it would not work.
My first attempt at a turn on my new hip careened 100 feet across the run, and into the edge of the trees with absolutely no control. After a little talking to self about wimping out, I did manage to ski the rest of the way down in reasonable form. The day the mountain opened, I started with a few pretty weak runs on the beginner chair, before the powder up on top beckoned strongly enough to overcome my lack of real power and trust in the hip. Once I got to the top, I did spend the next six hours skiing powder and crud non-stop.
The good news is that by the second season, most people were commenting that my resurfaced hip is skiing better and stronger than it had in twenty years. However, I will still change lines if I see a big impact coming.