Damn after the first 3 weeks I would have just turned the CEL off in the code. (j/k - I still have mine set to 1)
That's, umm, just, umm, great you fixed the 3 year old problem. Heck if you were strapped for cash you just could have spent $5 at radio shack and made MIL eliminators for the downstream O2's.
You folks do know that any CEL, even a soft code, will curtain timing advance and run the engine a bit richer. (a hard code is much worse of course)