"...the normal and natural one"!!!
If the modern finish that you describe (for a topspin FH shot) is so normal & natural, then why was it not in common usage until fairly recently? In the 35+ years that I've been playing the game, there have been at least
3 topspin FH finishes that have been considered the norm (not counting the buggy whip & variations of the reverse finish). According to one source, the WW finish has apparently been used as far back as Tilden's time. However, it has not been the dominant finish until modern times.
The 3 different "normal" finishes that I have employed are the product of differentt (dominant) grips and different swing paths. The amount of topspin employed has also been a factor. The dominant finish of the 60s thru the 80s (and earlier decades) was a somewhat abbreviated follow-thru that had the racket finishing forward & up. The doiminant FH grips of the time where the Eastern FH and the Continental grips. Only moderate topspin was used at the time.
In the early-to-mid 90s, my dominant FH finish became the over-the-shoulder finish. The dominant FH grips during the latter part of the 1980s thru the 90s were the Eastern FH grip , extreme Eastern/mild SW grips and, to a lesser extent, the SW grip. More topspin was generally employed with this finish. This OTS finish is still very common today, especially with players using an Eastern or extreme Eastern grip.
Since the SW (and mild SW) appears to have replaced the Eastern FH grip as the dominant grip in recent years, the WW finish has become much more common.
Robert Lansdorp talks about 3 forehand finishes in the modern game (with the reverse finish as the 3rd type):
The Three Forehand Finishes - Robert Lansdorp
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