buzz.lightyear
and with sids and ageing aircraft in general.... a stupid thing to do... it's all about risk management.
Have you actually done any spinning? If you have you'll know it's a low "G" manoeuvre. The highest "G" is in the recovery from the dive after recovery, and that isn't usually all that high.
Remember the original post was about doing spins in a C172 for instructor training, so spins being done by an experienced instructor with someone with more than just ab initio experience. A fairly controlled environment I would expect.
There's likely to be mores stresses and strains from flying in turbulence. Shall we stop all older Cessna's that need SIDs from flying in turbulence?
In the scenario mentioned in the first post, spinning a C172 could be considered pointless but certainly not stupid.