Quite possibly you had been expecting less of a film on the floor when you were seeing the rather thin coats of sealer. And, there are a lot of brands of satin finish poly, some more appealing than others. I have always (or at least for the last 15 years) used the Fabulon Brand satin poly. It has a nice glow to it, but I think, does not make the floor look like plastic. And I hate to say this but for easy floor maintenance you really do need at least 3 MODERATE coats of poly on a wood floor.
I would never try to apply more than 500 square feet per gal of any oil based poly finish. Too thick a coat will take months to cure hard, and this can weaken the finish. Your floor contractors methods of using the sealer are questionable in my opinion. I'll bet if you had taken the time to actually see some of his jobs, you might have not chosen him. Be sure to read my Hiring Contractors articles in the How to section of this web site. Just because the guy does High End work, doesn't mean a thing. Even wealthy folks can be fooled. Use your own judgment.
Oh, and here are a couple of pics of some of my satin poly'd floors. One with a stain and one with just the poly. Does your floor look anything like this ?
As always your Most humble servant, Joseph, the Wood Floor Doctor.
You may also find these articles helpful:
1. Floor Types And Finishes
2. How To Apply Oil Based Polyurethane WITHOUT The Pits And Bubbles
3. Custom Staining Wood Floors Without The Blotchy Effect
4. How To Sand Wood Floors Without Leaving Machine Marks
5. How To Take Care Of Your Health And Safety when Installing, Finishing, Repairing or Cleaning your wood floors