You can clean in conditions that would certainly be unsafe were you to use ladders, but the kind of winds we have at the moment make window cleaning with either method pointless.
I did one particular shop day before yesterday, by the evening they were in a dreadful state

But shop stuff has to be done regardless.
The higher you go in windy conditions, then the greater the risk, regardless of the system you use.
I use the cheap Unger poles (for versatility) and I've had them extended flat on the ground at well over 30ft and hoiked them straight up without a problem (apart from risking my back breaking

) and I can't imagine working in winds so strong they would damage the poles (not without damaging me first

)
Might be different with Fibreglass poles though?
these current conditions are some of the worst I've known

Ian