Vaughn Simon wrote:

What is wrong with folks learning at their own pace? ...and just
what "risks" are we talking about here?

Consider that some of those folks just like to fly, and want to
do it safely. The extra cost of the CFI is a small matter to them,
so they see no reason to rush a solo. They consider that "flying is
flying" and having backup in the right seat takes nothing away from
the experience. They are happy to have the CFI along to keep them
safe while they tool around in the air and learn at their own pace. They
probably have no problem absorbing the written material, but
realize that it takes them longer to learn the physical skills than
it would take a teenager. Further, they have no pressing need to get
their ticket in any particular time frame.
As a CFI, I have seen many students like this, and I would be
happy to take all I can get.

Vaughn

I think the concern is that some of those guys aren't as you describe. They
are doctors or lawyers who are going to get the ratings with an hour here
and a hour there and then they are going to buy a Bo and get checked out it.
Then they are going to fly even less and then a few times a year go on
vacation or for a golf weekend and they aren't going to be proficient.

On top of that I'll bet (and I have nothing to back this up) the drop out
rate for pilots that spread training over a long period of time is probably
higher. And God knows we hate to loose somebody that wants to fly bad enough
to start the process.