I think you can prove his point to a degree if you take the dog example. Specifically when said child doesn't already own a dog.

They could use the knowledge to either not get into the situation entirely or to embrace the situation regardless.

The former will always result in less trauma over time. Unless I am missing something. The latter is open to debate.

Thinking like this is regards to past relationships, I have prevented a lot of self trauma through experience with trauma.