Came across this by accident. Happen to be a member of Simon's church.
He doesn't really talk about this aspect of his past, but then he might not want to. He doesn't hide it either.
With regard to mentoring, the church is affiliated to the local branch of the Evangelical Alliance and Simon has a close relationship with many leaders of other local evangelical/charismatic/mainstream churches. The church structure includes an assistant pastor (who is of a very different background) and is administered by a committee with officers elected by the whole membership.
I know Simon is very shy of HFC being a cult. I would describe his teaching as "this is a Godly way to live - now check it matches up with scripture". Nobody has ever been "excommunicated" for anything, least of all disagreeing with the leadership (although, obviously we've had members come and go). I assure you that neither myself nor most of the other membership would stand for too much "heavy shepherding". Also, his wife would never let him get above himself!
The most important thing is valuing the Word and following the guidance of the Holy Spirit.
Hope this sheds some light.
Best wishes
Have fun
Hugh