In reply to Offwidth:
I’ve only done it once (but have done the Dubhs numerous times with the Abb). It starts quite a bit below the Abb, and has a small cairn marking it on the left hand side of a grass flat area, with a cracked immaculate Gabro slab above this flat area.
If you haven’t done the Dubhs before it’s probably prudent to go upto the abb point and then go back down to find the bypass. You descend some way down a gully/hillside (slightly worn) before taking a rising basalt / grass shelf line to meet up back the base of the Abb. It was very dry and good visibility when I did it, and I don’t remember it being particularly difficult just exposed. It’s probably not very nice in the wet.
However, all the harder scrambling and route finding on the Dubhs is after the Abseil/bypass, so avoiding the abseil does not make the outing easier.
After the Ab there is an obvious block on the ridge to be surmounted, which while a two move wonder is hard for a scramble. The most worn line up Sgurr Dubh Mor leads to a steep initially V shaped Chimney with good holds but is not just a ladder of holds, it needs a bit of bridging and thought. There is an easier line up before this but it’s not obvious.
Post edited at 17:06