I used to have a big 36' ladder I did palms on, when going up about half way that thing used to get bit of a bend and wobble up. The end had a chain that wrapped the palm trunk, now if it was windy it was even more bazaar ... I really hated that heavy aluminium ladder and sold it.
Where the two sections of the extending ladder over lap is interesting. Some have what's called flyover (where the extending top section is above the bottom section) and some have flyunder (extending top section below top section).
My ladder was a flyunder.
I think they should ban the flyover, I wrote the manf years ago and they didn't really give a hoot. What happens with the flyover is this ....
... imagine you are coming down the ladder. I'm sure I'm not the only person who steps on the rungs where the balls of your feet are (just behind the toes). Well as you get to the next set of rungs where the join is guess what? The rungs are set in about 4" and the amount of times you near slip coz now only the tips of your toes caught that rung, it's stupid, you have to actually consciously move your foot in further which feels very odd especially as your torso is leaning out more as your still hanging on the top section. This is dangerous and bad design but most predominant on extending ladders.
With the flyunder set up, as you come down the ladder the next rung sticks out further and you catch it easier with your boot and your torso gets put on a better lean ... the safer option.
I hope you understand, so when buying a ladder check which style the fly is, and buy the flyunder.