design: type parameters: pointer methods, clarifications
design: type parameters: pointer methods, clarifications

Change-Id: Id99fed0f8a980003139581fd5830a89b9a85f401
Reviewed-on: https://go-review.googlesource.com/c/proposal/+/253817
Reviewed-by: Robert Griesemer <a6752097faebf1f02d80107d77a9be009089afe3@golang.org>

golang/proposal,golang/proposal