Swing-start experience.
I think there is a fundamental trainng problem here that no one has so far mentioned. This relates to finding someone suitably trained or experienced to put in the cockpit during swing starting, especially on a land-away where even a pair of chocks might be hard to find.
The average PPL nowadays would;
1. have no experience of starting up on twin toggle magneto switches, (you start on the left one only and only throw the right one when she starts to run).
2. not know the two-person procedure for swing-starting, (called out between the two people engaged in the procedure).
3. be nervous of doing anything whatever in an ancient and unfamiliar tail-dragger.
Result: people starting engines single handed.
Then familiarity soon breeds contempt...
Broomstick.