Ahh, that piece of rigging is not about any kind of compression on the Tornado (I'm refering to the Tornado, altough the discussion is a bit broader..).

The small cylinder going from the bridle intersection and down to the pole is to restrict the maximum luff length of the jib with downhaul applied in a measureable way. As per the Tornado class rules.

Lowering the tip of the pole could be handy trough a dolphin striker, but hitting waves would be a consern. Also, most classes has a max luff length of spi's as well (The Tornado also has a rule about minimum height of tip above deck).

I think the names dolphin striker and pelican striker are much more memorable than 'compression strut'