Then maybe it is the non-ideal alignment of the lines/blocks in the internal boom setup that is damaging the Ronstan and Harken blocks. I did find that the "plastic" blocks of both makes really do not like skewed loading or skewed line entries/exists. That tends to eat away at the plastic sides and eventually break the block. Is that what happened with the blocks Macca ?

Personally I'm interested to have a cascading mainsheet setup inside my boot like you, but I don't have big bucks for blocks like you have. So that is why I'm asking, I need to build it using cheap blocks.

Wouter