Hi Guys
On the question of Science we can look at the energy of a clean.
Energy is avaialable in lots of different forms, heat , light, mechanical, electrical etc
If we use the standard carpet clean i.e pre vac, pre spray, extract with hot cleaning solution we are using X energy
Alternatively try the 'new' method, pre vac, pre spray, mechanically agitate , extract cold water.Now depending on how much agitation then this will use more , the same or less energy.
So basically the heat is being replaced with mechanical energy .
The biggest drawbacks in my view to the latter are the increased time, remember not much use saving 50p on Chems when you spend an extra half an hour agitating and just as importantly the inability of maechanical agitation to make up for the sheer cleaning power of heat.
Cheers
Doug