Correction, they are done laparscopically. I had mine done after my last csection. Like others have said to get the two surgeons in there at the same time is the only way to get them done at the same time.
I saw someone (in the last couple of days) who had both done at once. I would think the complications would include doctor privileges as the same hospital and of course... getting their schedules the same. But, the person who wrote of it said that it cost less because she got both done at once.