Thanks bg, my apologies for not devouring this entire post. I more or less skimmed it. A case could be made for using shop time only as the basis for hourly pay.
The only job I ever had that paid an hourly fee was when I was in high school and worked at Jones Beach for the summer. That paid me for the time I punched in until I punched out. After that I caddied at the black course at Bethpage, where the PGA is being played this weekend. You might be surprised how many duffers embarrassed themselves there just to say they played the Black. I had some basic mechanical skills and spent the next 6 summers thru high school and college cleaning and tuning oil burners, the dirtiest job available that the regular mechanics didn't want to do. I was paid per job and not hourly and socked away enough money to cover my living expenses thru college. The military was a monthly pay and my first real job was in the city where I commuted daily. I earned a salary based on the time spent in the office. I ended up as a manufacturer's representative in the sporting goods industry, which was another IC job. I was not concerned with how much I earned hourly but rather how much I earned monthly, which, for the most part, was considerable.
I retired from my last job, got quickly bored and found mystery shopping which is quite similar to being a manufacturer's rep except not close to the financial rewards. As a rep I did learn that the only productive time was time spent in front of a client. Preparation for a presentation, travel time and writing and submitting an order after a successful presentation were all necessary but not productive. This is pretty much true of mystery shopping.
I don't see this as an hourly job but if a lot of discussion has been made about it and a case can be made for shop time being the sole factor for per hour income. In that case, $60 per hour is a piece of cake.