Wow this was my first forum post ever, at what I thought was a dead thread. I'm glad there was some response.

@ Brian: I wasn't suggesting that song's mythical original writer (or whatever) associated either sister with bent or broom; just that mine is one interpretation of the lines of the Pentangle song (lets call a spade a spade here) which is in line with their re-presentation of other folk songs/ballads. (Though I do now see that I didn't actually mention Pentangle or BJ in my post.)

@ Stallion: haha, yes there is also a "grove street" here in Oxford with a similar heritage. Again, I was speaking in a purely Pentangle context: I know there wasn't necessarily a conscious sexing-up, and that those specific songs were chosen for revamping for their inherent dark and dirty charm.