gatekeeper rules syntax and logic

[twosk]

Hello, I am trying to find places where structural designer should design a large hole for many small pipes intersecting structural elements:

My initial logic was to find all slabs and pipes intersections, filter that have protrusion and Measure distance between only filtered pipes using gatekeeper rules.

How one measures distance only between failed elements? I know how to put filtered pipes to 1 place. But if I want meaningful results, I need to place same set of pipes in 2nd element set.

If I compare filtered pipes to all pipes I get quite many unnecessary elements.