Experience with my Brewzilla when using alot of hops is you get a nice thick layer of hop matter on the false bottom, but despite that I've never had any issues with it blocking the wort and starving the pump. However I do still get a small amount of hop matter getting through so still have to give the pump a good flush out when cleaning up to make sure it's clean. However on the Grainfather you will still have the 2nd line of defence with your main filter. Maybe a good whirlpool as well might re-distribute the hop matter on the false bottom.
I think this is because the Brewzilla doesn't use a rubber gasket around the edge of either the false bottom to seal it against the side of the kettle do get some 'leakage' of hop matter getting past the false bottom. I might get hold of a length of rubber gasket to see if I can make a good seal, and I've already ordered some mesh sink strainers to use upturned over the pump inlet to see if that helps stop any wayward hop matter being sucked in the pump.
To mid mind It is definitely much easier and I suspect better from a flavour perspective to chuck the hops into the boil rather than using a hop sock or spider even if clear up is a bit messier.