Something to do with humidity changes on cues shipped to Japan.
The tolerances are what I would call a "press fit" to use
machinist terms.
When I screwed my previous ultra joint II cue together the
last couple of turns gave a compression fit squeeking sound
which makes for one hell of a tight connection, and I believe
the secret to his famous hit.
Apparently he had some joint splitting issues on Ultra II's shipped
to Japan,(correction: no joint splitting issues, the wood swelled up
in the humidity and made them real hard to screw all the way together)
so he went back to his original ultra joint.
Perhaps drpjr could share some insight on this, however
I do not believe there has been any issue on ultra II's that
stayed in the USA.