From what you wrote in your intro and here, I'd suggest staying on induction until you don't want to, get bored, near goal, etc. Of course, written from the viewpoint of someone who was on a clinic plan that is based on '72 Atkins induction. Many members of the local support group have been on it for years, in perfect health.

This thread explains an "average" pattern: http://forum.lowcarber.org/showthread.php?t=365499
As a late 50s woman, with 60 to lose, I lost 12 total the first month (none the third week), six the second month, then 3-4 pounds most months until reaching goal. And my arthritis, joint pains and skin rashes disappeared! Will never eat grains again.