Yes, interesting comparison test, but if one half was drier than the other it is bound to look better. The true comparrison (in cleanability) would be to inspect once both halves were dry.
A couple of years ago I carried out a similar tesy with a colleague, in my home.
We have a largish kitchen with carpet tiles covering the floor area. I TM extracted one half with Crystal Green, he used DF on the other half. The DF half dried in about 2/3rds of the TM side. On drying out completely there was no difference at all and both resoiled at the same rate.
Dave.