Originally Posted by Perk
When the shield is completely closed the struts seems to relax or reduce their pressure.
That sounds like over-centre geometry: the struts are most compressed (and thus exerting the most force) just before the guard is closed all the way, and then extend again a bit (so less force) when the moving ends come closer the to body than the fixed ends, due to the length of the mounting brackets. This is good, because the strut helps hold the guard closed this way, rather than always pushing it open.
It could also be that it's just the change in leverage: with this mounting arrangement the strut is much more directly pushing the guard open when it is up than when it is down. That's a good thing, too.
Either way, it's not likely any feature or characteristic of the strut itself, but it's a good observation.