Thanks Michael for info.

I use instances also to have live mirror. I create instance and scale it -100% on X axis. Then I have negative mirror of positive source. It gives me live mirroring. No matter what I do on one side I have live version on second side.

Blocks helps also modifying screws for example or boolean cutters (holes for screws). So it`s possible to change every screws in machine with one modification and every screw hole with second modification (boolean cutter edition before cutting holes). So it`s kind of pseudo proceduralism/ parametric operation.