Which commands can work on block geometry without opening the block for editing (double clicking or blockedit command). For example I just tested dupborder successfully on a blocked surface, but trim does not work.
Also, which commands can work on block geometry while editing the block but using external geometry. For example, trimming a surface within a block with a curve that is not in the block does not work.
I want to devise a workflow where I can work on a block in-place or a copy elsewhere, but not have to open and close the block continuously to perform the edits and add and remove geometry every time. Trimming a surface within a block against geometry that is not in the block is a big part of this desired workflow.