I have to say that this video is very reassuring, because just last Saturday I discovered an issue with the 5-iron in my set of MP-4's that my local shop was unsure would be fixable or if it would be best served by replacing the clubhead (due to overbending of the iron).
That's the 5-iron on the right, 4-iron on the left. A little tricky to tell from the angle of the clubs (trying to line them up side by side), but the 5-iron actually has some substantial curvature in the hosel.
I've been playing these irons for 4 years now, and unwisely ignored the advice to have your lofts and lies checked annually if you're playing forged irons. In that time I've probably played somewhere north of 300 rounds of golf, and my 5-iron specifically has always been my "go-to" club for hitting low punch shots to get myself out of trouble. The ground in Colorado is pretty firm (especially in winter), and I have a fairly high swing speed so this is a somewhat extreme example.
It turns out that over the years my 5-iron has been slowly bending backwards until today, where it now actually measures half a degree stronger than my 4-iron (which is still at the original loft)! I knew my gap between 5 and 6 iron was large, but it wasn't until I went out this spring to create an updated distance chart for all my clubs (it's been years since I made my last one) that I realized just how big a problem there was and looked to find the cause.
It's reassuring to see the test where a club with very similar design and metallurgy (the MP-18, compared to my MP-4) could be adjusted that far without breaking, so here's to hoping mine can be bent back without overly work-hardening the steel. If not, then I suppose it's as good excuse as any to go out and buy new clubs!
Just tried to remove another Pure Combo. Regulated my compressor down to 60 psi, and used very short bursts. Still some ballooning on the top portion of the grip, and it took 3-4 quick bursts to get the lower portion to release. After the lower portion released, I needed to tug a tiny bit with added air pressure to get it off. This one wasn't permanently deformed from the ballooning though.
In my short experience with the Pure Combos, they seem to be unique in that more careful technique is needed for removing them or adjusting the orientation on the shaft. It appears that the thicker bottom portion of the grip clamps the shaft more tightly than the upper, and this force difference between top and bottom can cause the top portion to balloon if the right technique is not applied.
Of course, YMMV.
Just reading the title, I was going to say "Depends on how hard you hit that tree".
But going back to the subject. Back in the day... when Cast clubs first came out, you were warned about this very scenario. Cast clubs might be stronger, but were much more brittle and any modifications would be small and VERY carefully done. Forged always had a lot more wiggle room and larger adjustments could be made.
but I suppose the days, materials and construction methods have changed a bit where Cast clubs can be adjusted more than they used to.