JGA, all I can say to you is that it is a complete “Urban Myth” about playing with harder to hit clubs so you can get more feedback and really learn how to play this game better. This is so ridiculous that I cannot imagine it still being passed along from one golfer to another. If any player really wants some serious “feedback” then why not go back to a persimmon driver with about 1500 MOI, 15% less CT, a 50% smaller sweet spot and 43” long? Regarding irons, there are currently a few blade designs that are actually as bad (read as low playability or very hard to hit) as the irons designed and sold in the 1950’s. I cannot possibly imagine telling a player that if you really want to get better then you need 50 year old iron technology. It’s almost like saying, “step up and be a man”, just try and hit it.
Every golfer should be playing with a minimum playability factor of “Game Improvement” and I personally will always stay in “Ultra Game Improvement” because I want to play my best and have the most help I can get from modern technology. I still wonder how good I could have played in college with modern clubs and balls. My 1961 Wilson Staff’s 2 through PW with normally slippery leather grips and in the lowest playability category of “Player Classic” were quite a handful.
Finally, here’s the bottom line; with any playability level clubs you choose, you will still get a comparative level of feed back on shots that are not perfect. You will always know if the shot was good, not so good or bad. The result of the shot however will be much better from higher playability clubs than from lower playability clubs. So, for example, the toe shot with a “Conventional Playability” 6 iron that landed in the right bunker and felt unsolid may possibly clear the bunker and land on the right side of the green with a “Ultra Game Improvement” 6 iron, but it will still feel like a toe shot only not quite as unsolid as the lower playability 6 iron.