From what I understand every clinic/insurance/doctor has different requirements. We are in the middle of the process right now. (I say "we" because my husband and I are doing this together....his surgery is 5 weeks before mine.)
I called the clinic in August to schedule a consult with the surgeon. They informed me that my insurance requires 6 months of "supervised diet". We began doing that at our clinic, visiting them once a month for weigh-ins. We went to a mandatory seminar and consult with the surgeon on the same day. Within a few days of that, the clinic called us to schedule surgeries and mailed us our "itineraries". They did all the scheduling for us. So, they scheduled clearance with our PCP, EKG, nutrition class (1 visit), psych consult (1 visit), and pre-op testing. Meanwhile, we keep doing the last couple of months of weigh-ins to satisfy the insurance requirement. The clinic feels we shouldn't have a problem with insurance or med clearances. We'll see what happens.
Lucii - considering that every place is different....what your clinic is asking you to do doesn't sound too unusual. Even post-op instructions will be different depending on your surgeon. I hope this helps!