How strong is yak leather?

A question relating to Children, Leather Sofas, and Leather Coats...?

• Many wealthy people with small children have leather sofas with the reasoning that it's easy to clean spills off of leather sofas. If leather sofas can get wet and be cleaned easily, is the same true for leather coats? My line of questions is leading to my main question...Can leather coats be safely worn in the rain? If not (which is what most people say), then why? Why can't leather coats be made as durably as the surface leather on sofas?

• Answer:

  Real leather can tolerate a few drops of water which have to be cleaned off quickly. If the leather isn't properly conditioned every 6 months, water spots will leave rings and stains. Very cheap processed leather furniture is so over processed it's more like plastic than leather and it can tolerate water and juice as it's coated, not true full leather. So a real leather coat, if exposed to rain would get wet all the way through, not just a few drops. And wet leather gets hard and shrinks.