Hi Darryl,
I've taken some shots in the past with my Sony Cybershot sitting on a tripod on top of my EQ platform. They're great for widefield shots and you're right, that at short focal lengths, tracking inaccuracies don't really show up as much until your exposures are quite long.
Ideally you'll want guiding though, with the camera piggybacked on an ED80 or similar on an EQ mount (HEQ5/EQ6).
This image and
this image were both taken in this fashion, but without guiding.
The camera was just mounted onto the EQ mount or piggybacked, but I had no guiding at the time. They were 5 minute exposures and in the full size versions there is some minor trailing.
Nowadays when I do the same thing (hopefully at SPSP next weekend) i'll be guiding at the same time.