Here's a brain tickler which may be easy for those "in the know."
I'm arriving Heathrow airport and have business in Guildford, Surrey. I wish to make the journey as rail-centric as possible.

The NationalRail journey planner advises utilizing the Heathrow Central Bus to Woking - a 45 minute journey on a good day. Followed by an 8-minute sojourn on rail. Too much bus, not enough rail.

Please advise of a path , not ridiculous in length, that is all rail from Heathrow to Guildford (include tube if necessary).

Thanks!