Papa Matt-
I think the only disadvantage to using Tru-oil is getting it stuck all over your hands!
That stickiness would be the varnish resins that are added to bind with the oils to form into a thin, light film. Most people on this thread use many coats. That would be necessary to build much of a barrier to
moisture vapor. But, even one coat would provide a short term resistance to water, liquid or vapor.
If this finish works for you, use it.
, that's my opinion!!
P.S. disposable gloves help alleviate that disadvantage!