I think that I may understand why so many golfers "feel" like the hosel is rotating around the sweetspot post-impact.
As Yodas Luke pointed out, if one rotates the club in a lathe, the axis of rotation would be through the COG of the clubhead (sweetspot) and the hosel would rotate around the sweetspot. In other words, if a golfer "feels" like he is rotating his clubshaft very actively through impact, he may acquire the "feeling" that the hosel is rotating around the sweetspot. What would cause a golfer to rotate the clubshaft actively through impact?
I believe that many golfers over-rotate their hands through impact under the mistaken assumption that one should have a supinated left hand post-impact, and that the clubface should be facing slightly groundwards post-impact. AJ Bonar teaches this action - called an active hand crossover release action.
AJ Bonar uses this composite photograph to make his point.
If you mimick that hand swivel action through impact, then you will certainly acquire a "feeling" that the hosel is rotating around the sweetspot.
However, the true wonder of Homer's work on hinging actions is that he demonstrated that there should be no swivel action during the followthrough phase, and that the finish swivel action must be delayed to the post-followthrough phase of the swing. During the followthrough phase, there is a small amount of clubface roll-over when utilizing horizontal hinging action, but during that HH action the left wrist remains vertical to the ground. In other words, the left wrist does not supinate during the followthrough phase, and there should not be a "feeling" of the hosel rotating around the sweetspot.
Consider this birds-eye view of Jack Nicklaus' swing.
Between impact and the fourth parallel (images 1-4) the clubface rotates 90 degrees. However, the hosel does not rotate around the sweetspot - because the clubshaft is always kept in front of his rotating body (butt end points at his navel) and there is no independent hand rotation. Note that the back of his left hand is vertical to the ground - as if there is a vertical hinge mounted in his left shoulder socket allowing the entire left arm-clubshaft to rotate at the same rpm. If more golfers pivoted as well as Jack Nicklaus post-impact, then I think that there would be less sympathy for the idea that the hosel rotates around the sweetspot post-impact.
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