I thought this was one of their weak points and that they slithered all over it being unable to cut through.The old school of thought was that a narrower tyre was better for that reason.
Please enlighten me.
Opposite way of dealing with the problem.
There’s 2 types of grip, friction derived from the trail and the tyre compound. And mechanical derived from the ability of the tread pattern to dig in and not slip. In mud it’s mostly the latter.
In deep mud the tread pattern will work up until the point the shearing load on the mud exceeds it’s ability to resit it. i.e. the tyre doesn’t slip, the mud slips over more mud. A CX bike works on it’s ability to exceed the shear in a vertical plane and sink down to ground solid enough not to shear in the horizontal plane. A fat bike works because you have such a big contact patch the horizontal shear doesn’t exceed the mud’s ability to resist in the first place.
Normal MTB tyres sometimes struggle as they can neither dig down or spread the load sufficiently so you end up just paddle wheeling through.
It works. Although I’d caveat that with “it depends on the mud”. They work brilliantly on fast muddy corners where they carry speed, but show them a long steep muddy bridleway climb churned by horses hooves, and the CX bike will storm ahead.