Hi Chaps,
It sounds like typical new stock teething troubles to me rather than any failing with the locos and stock. Sure, the RETB faults and driver rostering should have been sorted from the start, but that doesn't mean that the idea is not sound.
If Cl67's are cleared to operate to Fort William (as they clearly are), they should be more suitable than Cl37's. After all, they are far more powerful and have a higher top speed. If they have any handicap (and I'm not saying that they do), it's possible that they don't grip as well because they are driving through four axles instead of six and trying to put down more power than the venerable Tractors did. However, that should mean that the axle weight (total weight of loco divided by the number of axles it has) is higher with a Cl67 which should mean that it grips slightly better.
As for hitting debris, I would echo what others have said about the miniature snowploughs. They are there just to deal with relatively small build-ups of snow and nothing more substantial, as they are of comparatively flimsy construction. If the Skip suffered a damaged ETS connection, it would suggest to me that the boulder was of a size and in a location to have inflicted similar damage to a Tractor, whether it had snowploughs or not. However, if these Skips become a regular fixture, I imagine that miniature snowploughs of some sort will start appearing before very much longer.
one TN