Besides getting laughed at by your co-workers and cursed at by the
person who tries to get it apart, what's wrong with soldering a
threaded connection?

A co-worker was telling me about his first foray into the world of
sweated plumbing connections.

He was a installing a new shower valve which involved a threaded
connection at the valve and then sweated fittings after that.

He got everything installed and sweated but when he turned the water
on, it leaked at one of the threaded fittings. He looked at the
situation, realized he couldn't tighten the connection since
everything else was soldered in place, so he took the easy way out.

He grabbed the torch and sweated the threaded connection.

Is he looking at problems down the road?