Doug,
I can't say one way or another whether the relationship was linear or non-linear back in 1985. Who knows?
Would it be deskilling to go to a place where the relationship was significantly non-linear - I think so. I believe it is a skill in driving to be able to repetitively deliver the sweet spot more or less square to the ball at high speed to achieve the longest drive possible and to keep it in the fairway. Does it require more skill to do that at higher speeds and longer shafts? I think so. If we negate the benefit of increased distance, then that negates a fundamental skill.
No doubt the modern approach to driving for the pros is to find the right launch angle and spin rate to maximize carry and minimize rollout. Get the max distance and hit a target and try not to let it roll from there into too much trouble. Now, even the pros don't do that all the time. It's not a good approach for windy conditions for example. I wonder whether players of even 10 or 15 years ago even thought about launch angles and spin rates? I know I didn't. Has that understanding and the optimization of launch conditions with technology led to greater distance. Absolutely. I'd have to think that even if we didn't have modern balls and drivers, that people would still have figured out optimization and increased distance with it, even with old equipment. Not to the same degree as with modern equipment, though.
You must play a different game than I do if all it takes to drive well is to:
Just get the right ball and correct driver loft for your swing speed and natural launch tendencies, and you are golden. No messy business using skill and hours of practice
I've spent three years and gone through launch monitors, fitting sessions, spent hours researching the technology and fitting, and built or bought 8 drivers to optimize my driving. I've also video-taped and analyzed my swing and spent time modifying it to hit a draw after 40 years of fading/slicing the ball. Although it is certainly better than it was 3 years ago, it's hardly golden. You can't buy driving skill or any golf skill. You can certainly use technology to enhance the skills you have. But if you could buy a skill through technology, then the tour pros should be perfect, because they sure practice enough.
The non-linear example you give is not necessarily bad. For my logical/scientific mind it doesn't seem fair. Why is it good?
As to altering my swing, I do it frequently depending on the conditions. I try to hit low balls into the wind for example. And draws on some holes and fades on others. Notwithstanding the common wisdom, the modern balls still bend, at least for me. Often unintentionally so
For whatever it's worth I don't pound it out there 330 yards and I don't generally flog my way around the course. My course is punative. And I don't have enough LW skill to get out of the places I could flog it to.
As to fitting the swing to the equipment, isn't that what players do with any generation of equipment. Certainly 80's golfers had different swings (and therfore skills?) than hickory players. Is the 80's model the best swing skill that we should aspire to?