Ed Huntress writes:

Are you taking this from the ANSI/ASME B1.20.7-1991 (R2003) spec,
Richard?

Yes, via MH.

I don't have access to that stuff these days, unfortunately,
but is it something in there that leads you to say it can't be tapped
or die-cut?

Yes, as my earlier post stated, the features of the *nipple* (male
component) and the *coupling* (female coupling) include not just the
thread, but also a pilot, a relief, and a different lead-in thread angle.
That's not to say you can't tap or die-cut the .75-11.5 thread itself, but
that thread is only one feature of these couplings. The other features
require (as standard states) cutting, rolling, or thin-wall forming, not
tapping or die-cutting. So a tap or die alone will not do it.