Interesting, however the author did not mention WHY Jack Lott didn't just use the .450 Watt's case, a long time wildcat on the full length H&H case, which is identical to the case on HIS .458 Lott.

The "Lott" chamber, if cut correctly, has a gradual angle from the 'end of the case' up into the leade/throat of the chamber. This is so if shooting .458 Win. Mag. ammo in it, jacket material is not scraped off by the 90 degree normal end of the chamber angle up into the throat. That is the only change form the Watt's chambering.
I read about this back when jack Lott brought out the Lott chambering, as why - an article, by him.