Hi JMJ
There have been many references on the forum relating to the agitation of pre-treatment chemicals.
I think that you will find that most cleaners who use a mechanised system have a machine with contra-rotating brushes...there are various makes around including the 'old style' Host machine, Sebo do one and I am sure that other 'Cleanituppers' will come up with a few more..
Hope this helps
Derek