If the track you mention is the one from the Tolsta road end (the bridge to nowhere) to Ness it's barely passable on foot. The first mile or so is rough track, once that peters out you're yomping through peat from one marker post to the next with bog as an added hazard.
EDIT - I'd not realised in spite of many visits that the beach at the road end was known as Garry beach. We are speaking of the same place.
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