Sepp holzer growing cépes from sawdust

I just read sepp holzer's book on permaculture at krameter hof.
He claims he has found a way to inoculate trees with sawdust he places around the fruiting bodies. He says its a succesful technique.
Never tryed it myself but could I belive him?
I know that the INRA , French agriculture researche institute did tests to inoculate trees with porcini with no result.
If Sepp has found a way to inoculata trees this way, i think he would be filthy rich now. ( if he wanted to / inoculated trees would be easely availeble in europe, witch is not)
Any one who wants to share a comment on this?

Traditionally, the standard view was that it was not possible to cultivate mycorrhizal mushrooms. Paul Stamets talks about how Frank Herbert?, the author of Dune, was able to semi-cultivate chanterelles on Douglas fir trees in Washington State. I would be very interested in some kind of confirmation that this is really happening. I know cep/pilz/porcini/king bolete is one of the most loved mushrooms on the planet, but they are very expensive currently, due to the lack of cultivation.
John S
PDX OR