[lamchob]

Maybe, but a real challenge of circuit layout and routing is that you want to generate (mostly) planar graphs, since your options for intersecting connection lines are limited and expensive. For the TSP, this does not really matter since the problem is more abstract.

[sigmaprimus]

Interesting point, TBH I had never considered applying the TSP to any more than two dimensions, as it becomes exponentially more difficult with each node added even within the same plane. I'm not even sure if adding more dimensions would make it more difficult or not but You have me thinking on that now, so thank You.