Yep,
That circuit is essentially the same as the one in the G9/Diy psu, but will only work well up to +160V.
In the G9 psu, there will be reduced voltage at higher current because - and only because - the second resistor/capacitor filter combination (i.e. after the regulator). Because in the G9 we don't worry about this.
Loose the second R/C filter - or reduce the R - and it will be plenty of stable for vari-mu applications. I know. :razz:
Jakob E.