I would think that in the old days, it was a lot more work to make up an end sealer. there was probably less need to as they would cut and put them up quickly. I wonder if back then they were using more old growth heartwood that has less tendency to check naturally. We probably are using younger timber today witch may be less stable. This is just a theory on my part. Today we have the advantage of having end sealer readily available and can use it to reduce the checking. Reducing checking is a benefit that is a positive to be taken advantage of.

One other reason we care more about checking today is simple aesthetics. In most old timber framed homes, the timbers would be hidden in the walls, and in barns, one wouldn't care about the appearance. In modern timber frame homes, the timbers are left exposed - celebrated for their beauty, and we do we can to make them look better. CB.