I agree with everything said so far.
In addition, I think it's important to understand the "normal" flight envelope, and to understand what happens if you push that envelope up to, and just past, its limits.
For most PPLs, once they've completed their training, stalling will not be a normal part of the their flying activities. Slow flight, though, definitely will be - every time they land. Therefore, it's vital that they not only understand slow flight, but also what happens if they get too slow, i.e. stalling. That is to say that the student understands what happens if he pushes the slow flight envelope too far.
Llanfairpg asked about spinning. For the average PPL, having a sound knowledge of stalls and stall avoidance is sufficient. The average PPL will very rarely set out to stall an aircraft, so with a good knowledge of how to avoid the stall (as well as how to fly in balance, of course), spin training is not really necessary (although there are always students who want to experience it, and I was always happy to teach students spinning, but only if they asked me).
On the other hand, us instructors are regularly expected to stall aircraft, so it is important that we understand what happens if we push this stall envelope too far (or, more likely, our students mess up). So having spinning in the FIC syllabus seems, to me, to be the right compromise.
But then I wasn't around back in the days when the PPL syllabus including spinning, and I know there are some strong feelings from those who were!
FFF
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