Always get a chuckle out of "put it in a vice and hit it with a hammer" welding strength test. That is a "feel good" test and not scientific in any way. But if that gives a builder a piece of mind I guess go for it.
Always clean the filler rod and metal with MEK or Acetone before TIG welding. I even wash the inside out. No oils or mill scale at all. The big three things that go wrong when TIG welding....