John,
I assume the offer is a client confidence builder, that demonstrates how strongly you feel about and stand behind the quality of your work. Which is good. It feels however, like "over trying," which does not stand for confidence.
Also, the procedure is cumbersome. IMHO most clients will not go through the hassle. And if they do, it may prove to be problematic.
In our experience, all most clients really want is someone that will show up on time, clean to the best of their ability, take the time and make an effort and handle complaints (in the unlikely event) promptly and gracefully.
That's only my opinion. I may be wrong. Try it.
P.S. I hope this is not too cryptic: Lee is just being Lee. He can't help it.
I've loved Lee and his comments for a long long time and will continue to do so.

