Did it for the first time at the weekend. It would be possible to do it on a 100mm hardtail, as with many things it depends how good you are on a bike, and what bike it is, a 456 Summer Season would be better off than a racy hardtail.
There are some fairly challenging bits – similar in technicalness to the Laggan Black run IMO, but in much longer sections than at Laggan. The first third and last third would be fine on a HT, the middle bit might be a bit more challenging,