Make sure sample show before/after parallelizing

> I went through part of the application example and ran into the fact that it seems like the example is already the parallelized trace, despite what the docs suggest. Is that expected? It seems like it might be nice to have it be able to produce both kinds of traces so that someone following the tutorial can actually explore the comparison features, etc.

Start by locating the application example referenced in the documentation and compare its current trace with the documented before-and-after behavior. Determine how the sample could expose both sequential and parallel traces; done means the tutorial can produce both traces for comparison.

Written by the indexing model from the issue text.