I have bent mine as well, but I think it happened when I fell backwards into the cockpit once and landed on the stick.
It's bent right at the end, so there's no impairment of the telescoping function (except, perhaps for the last fraction of an inch).
I hear you on training new sailors. For doing daysails I don't always need "active" ballast, because with several people in moderate winds the "static" ballast can be very effective on its own
I normally position myself in the middle, so one guest can handle the jib sheets and another the tiller, but I can reach both and switch to "single-handed" sailing as needed. With more people on board, I'll hand off the main and after that invent "necessary" tasks. Sometimes we need to divide a bit unevenly by weight to get the right trim; with more people in the boat that can get interesting during a tack... one time the smallest one had to duck into the cuddy so we had enough room to move...
If it's necessary to sit out, I'll usually start, next thing is to get the youngsters at the jib to do the same, and some people will just never be comfortable.
But even for those that get the tiller, it's really hard to handle the extension. The difference is that the tiller gives you direct feedback when it is in neutral position. With the stick, you lose that - it's similar to using a wheel where you may not know whether centering the little mark means that the rudder is centered or whether it's still a revolution or two off center. Most people new to sailing (or boating in general) do assume that a boat tracks like a car - they want to hold the tiller at center for making the boat track straight. They need to acquire the feel for the need for constant small correction, the fact that the boat is actively balanced by the rudder.
Sailing with people trained on keelboats is really interesting. They may get sail handling, maneuvers and even the tiller, right away, depending on their previous experience, but they have literally no concept of what follows on a 30 degree heel on a dinghy if nobody takes quick action
They are also totally unconcerned about cleating sheets or falling off with the sails tight....
OK, back to "single-handing".