Hi. I'm a local to this area. I am aware of one peice of folklore which gives us the origin of its name. At the time of the plague, farmers that lived and worked outside of the town used the stone to trade their goods with the infected towns folk so as not to get infected themselves. There was a certain amount of trust involved with the transaction. Fresh produce would be left by farmers then collected by towns folk. Money would be left at the stone as payment. Nobody would need to make contact. If money was not left, no food would be there the following day/week. The majority of the produce left at the stone was wheat. Over time the word wheat has lost the 'a' which gives us the word 'Whet'.
Hergest is most definitely pronounced Har-guest.
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