@riobard I think it boils down to the fact that I am lazy, plus it is so darn convenient to just use `%v` everywhere.
Then, whenever I am debugging structs, I use `%#v` (which never shows up in the repository, of course).
And whenever I am debugging protobufs, I use `"...%v", proto.MarshalTextString(p)` to get a nice dump of the protobuf.
In code reviews at work, I almost always see `%v` in Go code except in tests where `%q` is used in case quoting is necessary.
Granted, I'm not the Go authority, but that's been my experience.  Feel free to take it with a grain of salt.  :-)