Are data pin chains re-executed with every access?

It is very common in Blueprints I see made by others that data pin nodes will feed into multiple other nodes.

For example, consider this code from the Blueprint Fundamentals docs:

Break Hit Result is presumably chained into a Trace call or a Get Hit Result Under Cursor. There are five different connectors running out of the Break Hit Result node. Does this Blueprint result in 5 unique traces, one for each time the chain is called upon?

If so, is there something about Blueprint under the hood that makes these many extra calls acceptable, or will it happily devour processing power with repeated calls?

As a corollary to this question, does this behavior differ for Execution nodes that provide data pins?

Just thought of something else, too… what happens if I have a function that returns multiple variables? Is the function called once for each variable read??