Given all your efforts that's really disappointing.
Having some experience in writing operating procedures and instructions, they are meant to be written so that they can be understood. Any safety issues are usually highlighted separately.
Many people buying trekking/walking poles are truly beginners and have no experience with their care or maintenance. Unless told about this at the time of purchase or by an experienced user, wrapping with its copious advertising is usually discarded. I know, I know but who reads instructions? Confession: I do but we have a saying in Australia if all else fails, read the instructions!
Then there's the issue of whether you are mechanically minded - or not. I know to maintain and adjust trekking poles only because I'm pedantic about reading instructions and fineprint. My husband knows because (in his own words) I'm a boy!
I'm grateful for the heads up and timely reminder to check on my own collection of trekking poles.
PS I have a pair of pacer poles which come with detailed and copious instructions on use, maintenance and adjustment.
Because this thread is entitled "TREKKING POLES SELECTION", I wish to underscore your reference to "pacer poles" aka "
PacerPoles," which I enthusiastically recommend.
http://www.pacerpole.com
They can be obtained online from Britain. There are also YouTube videos showing how to use them. Their handles are quite different from other poles, and they are very comfortable to use.
I used PacerPoles last year for nearly 1000 miles on the
Camino Frances, Camino Portuguese and Camino Ingles. Before that, I used them on a difficult hike in the highlands of Bali. I am 70+ . These poles have been a major contribution to both my safety and my comfort.
Here is a review I just found online:
http://sectionhiker.com/pacer-poles-why-arent-all-trekking-poles-this-good/
It begins:
"British-made Pacerpoles are far superior to the trekking poles you can buy in the United States. I’ve been testing a pair for nearly 2 months and I am a convert. They help me carry a backpack with better posture, prevent muscle soreness in my legs, and are much more resistant to bending and snapping than my current trekking poles.
The main difference between conventional poles and Pacerpoles is in the hand grip. It’s kind of hard to explain so I’ve shot this video to show you. Instead of a vertical pole grip, the Pacerpoles have a horizontal pistol style grip, where your thumb is positioned at a 45 degree angle to the ground and the ball of your hand is on the top of the pole. These two changes give you a much better mechanical advantage to use the poles for propulsion and lift, rather than just lateral stabilization like conventional hiking and trekking poles."
I suggest reading the entire review, which also includes:
"If you decide to take the plunge, Pacerpoles has an unlimited 30 day return policy which may or may not give you enough time to decide whether you like the differences or not. Either way, you really need to commit to these poles to get any benefit out of them." AND
"
Conclusion
I am very impressed with the aluminum pair of Pacer Poles that I tested in this review and I’m glad I finally tried them. Honestly, I will probably buy a pair of my own rather than continue using Black Diamond trekking poles for three season hiking. The Pacerpole hand grip makes such a difference in my posture, walking speed, and stability that I can’t imagine settling for anything less. If you climb a lot of mountains, you should give Pacerpoles a try. I would recommend sticking with the aluminum ones, only because they will be more resistant to breaking and they are likely to still be usable if you bend them. I’ve snapped way more carbon fiber poles than I ever want to and don’t trust them in very rocky terrain."
My own discovery of PacerPoles was through this Forum, which I explained in an earlier post:
"I do not think I would have completed the Caminos without them, because I had several long stretches with a problem with my left leg. Others in my family have also used them with similarly positive experiences. I tried them after reading a lengthy thread asking something like "Does anyone NOT like PacerPoles?" They are made in the UK, and there is a 30 day trial period. Learning to use them is relatively easy. The instructions and the videos are reasonably straight-forward. With their special, angled grips for the left and right hands it is difficult to use them improperly."
In short, I think PacerPoles are worth considering.