I will have to look in my Hogan achieves for additional information.
BerntR is correct in his Nicklaus observation, but it was short-lived during the early 1980's. For whatever reason, Nicklaus for a brief time used a grip that was weighted in the grip end.
I read that too . . . . there is a company that you can buy "back weighting" for the grip cap of the club. I know ECox did it . . . said it made a big difference. I'll see if I can find the company. Their big push was putters but you could buy the thing for irons. I think Nicklaus put a dowel in the shaft and then filled it with lead shot or something.