Howard I have to say what you've done was on the risky side and were lucky nothing went wrong.
After TPLO, which involves sawing the tibia bone in two, the healing of that otomy takes every bit of 8 weeks.
Professional rehab as I know it from the U Tenn program do have the dogs doing quite a bit by 8 weeks but unlimited field work at 8 weeks may be reckless.
The fastest rehab I heard about was 10 weeks by the late John Sherman on a dog whose owner wanted to run the National. This was not home rehab but cutting edge stuff done but the best rehab doc.