Higher Tows for Training Flights

As some of you know, I'm working on my CFIG (should get it after
contest season is over). But I have some strong disagreements with the
way my club handles instructing and so I'll be going my own way once I
have the cert. One area I've been thinking about a lot is our 3000-
foot "standard" tow. This seems to be a habitual height for a lot of
operations in the US; but just because it's a good height for catching
a thermal doesn't mean it's a good height for instructional tows...

Are there any clubs or operators out there that make high tows (say,
5000') for instructional flights? If so, can you provide any feedback
on how it works "in the real world"?

My thinking goes like this:
1) A high tow to 5000' doubles the "working band" for the
instructional flight. If you reserve 1000-1200' for the pattern, then
a 3000' tow gives you only 2000' (max) for maneuvers. A 5000' tow
gives you 4000' for maneuvers.

2) In the powered-airplane world, training flights are often set to
last 1-1.5 hours. This lets the student practice a maneuver multiple
times in a row and either work out some kinks or polish their skill.
With only a 2000' slice of air to use for a standard glider training-
flight, the student is often rushed to complete clearing turns and run
through a set of maneuvers just one time. There's little-to-no time
for multiple attempts. By contrast, a 4000' chunk of altitude gives
you about 18 minutes for maneuvering (assuming a roughly 220 fpm
descent-rate; which seems like a reasonable guesstimate for a training
aircraft doing a mix of turns, stalls, and min-sink maneuvering). 18
minutes should be enough time to let the student settle-in to the
flight and make 2 or 3 attempts at a couple of different maneuvers,
plus catch their breath and actually prepare to come into the landing
pattern (instead of trying to speed them through the checklist). I
think there's a tremendous amount of value in repeating a maneuver
multiple times in a single flight: it lets the pilot work through
issues, experience a sense of improvement, retain information better
(including muscle-memory), etc.

3) If the student is in early training (not able to handle the takeoff
or the landing), maximizing the "maneuvering" portion of the flight
really gives the student the best bang-for-their-buck. 5-8 minutes of
aerotow plus 3-5 minutes of landing means that - on a 3000' tow - the
student only has the stick for ~50% of the flight *at most* (less if
the instructor takes the stick to demonstrate anything). With a 5000'
tow the student has the stick in their hand for almost double the
amount of time (roughly 9-10 extra minutes). If you look at the tow
fees for most operations, an extra 2000' of altitude costs less than
the cost of a whole extra tow. Unless the student is at the point
where they're working on their landings (when they could be taking
pattern tows), this seems to be a better way to maximize student
practice and minimize their costs.

4) Time savings. If you're a student (or an instructor) trying to
slot into a long launch line and/or have good pre-flight and post-
flight briefings, you're going to need to be at the airport for 8-10
hours a day to get 3 flights in. During those 3 flights, you the
student might get 30-45 minutes "on the stick". A single 5000' tow
gives the student roughly 18-20 minutes "on the stick"; so they can
achieve the same amount of "stick time" in only 2 flights (two high
tows or one high and one "normal" tow). In today's busy, modern life,
I can see a compelling argument for instruction that allows busy
individuals to get 2 good flights in during a morning or afternoon
(i.e. half-day) session; rather than hanging at the airport all darn
day in the hopes of getting that third flight in before dinnertime
(and if they only get 2 flights in, their 20-25 minutes on the stick
is really close to a single high-tow flight, which they could have fit
in during a short 2-3 hour session at the airport).

The only obvious down-side to this scheme is that your towplane and
your two-seat glider cycles a little bit more slowly; but I firmly
believe that the glider community needs to stop focusing on quantity
of flights and start paying more attention to QUALITY of training.
Making competent pilots in fewer flights means they get to the fun
part of soaring more-quickly and are (hopefully) more-likely to stick
with the sport. And although you might get a couple of less students
in the air each day if they're all taking high tows, they're still
getting a good amount of air-time and (hopefully) earning their
license faster so that over a period of time (say a year), you wind up
training just as many (if not more) pilots as the "old method"
involving lower tows.

Any thoughts, comments, or flaws in my logic? Any "gotchas" I'm not
considering?

--Noel