Resto Shaman BGs (Classic & TBC PvP)?

I know Resto Shamans are bad in Arenas in TBC, but are they good in BGs? How about in Classic/Vanilla? Is this a bad class/spec choice for someone who likes to spam BGs and healbot everyone, stand in the back healing the group and staying alive, etc? Like a traditional BG healer.

I’ve only played Priest and Paladin, which I love, but I wasn’t sure about Shaman. Thanks.

Shamans are great in world PVP and BGs. They just suck in PVE DPS. They are also great PVE healers.