That's not what I said. I said the effect it usually has is to reduce throw.bud02:
For you it is a rule of thumb. IS english has no effect. Your statement below.
I guess by "slip" you must mean throw, although it's kinda hard to tell. If you're saying that inside spin only reduces throw with extremely thin hits, then you're mistaken - it happens on any cut angle with more than about 50% of maximum sidespin and on any cut angle of 30 degrees or more with any sidespin (as I said in the beginning).IS english certainly does induce slip but you reach a point on the outside of the OB that it has a minimal effect where IS english acts like "speed" reducing slip, BUT IT'S AT THE EXTREME EDGE OF THE BALL.
I disagree with your statements - you made them.I think your looking for a disagreement.
pj
chgo