Wes,
Ocasionaly when welding a loosly fitted parts togather, a crack will develop because the inner will pull from the cooling stress on the other side from the arc, and a crack will follow you right around the job.
In that situation, you have a real mess because another bead will likely crack too.
Some engineers recommended several heavy "tacks" around a job.
If one weld cracks, the crack will stop there.
I would recomend at least "size to size" fit.
To each his own, good luck.
Kap