"Straight" talk

@stringreen sorry, too clever for me 😀 I’d assumed you were referring to the classic horizontal cartridge top when viewed from the front! Now you explain it makes sense

lewm

... on average, one might be better off with ignoring azimuth adjustment in favor of setting the cantilever 90 degrees with respect to the LP surface.

I absolutely agree. Moreover - although every aspect of phono cartridge alignment geometry is important - I do not think that azimuth is the most critical. Much, much more important is assuring that the cantilever/stylus is truly tangent at the chosen alignment's null points. Gauges that align the cartridge rather than the cantilever are particularly vulnerable to getting this wrong. That's why I always suggest the use of a mirrored gauge, such as the WallyTractor or Mint gauges. These use the reflection of the cantilever itself to ensure proper tangency. The only better way, imo, is to use instruments, such as an oscilloscope.

I've been all around the block with azimuth, aided and abetted by the fact that I own a Triplanar, which was once one of a very few tonearms that allowed precise adjustment of azimuth (albeit while messing up zenith).  (Nowadays, there are many tonearms or just headshells that offer this feature.)

Plus, I own a Signet Cartridge Analyzer, the grandfather of the Foz.  While obsessing over crosstalk using the Signet and the Triplanar, I found I was occasionally messing up the sound by canting the cartridge extremely to one side or the other in order to make the meter on the Signet happy.  This was the case in particular with my Koetsu Urushi, which was canted way over, like folkfreak said, in order to achieve best crosstalk numbers.  When I just gave up and set the Urushi so the cantilever was perpendicular, the sound was and is a lot better.  Maybe crosstalk isn't optimal, but all else is copacetic.  Now I have become a nihilist where azimuth is concerned.  I think a lot of this has to do with the perfection or lack thereof with which the coils of the cartridge are positioned inside the body, which is something one can not directly observe.  If the build was flawed, then pushing the azimuth to fix the problem is not without its cost to overall sound quality (and probably aberrant stylus wear).  I don't claim that it is not a good idea to have crosstalk maximally adjusted when possible.

Re results that end up canted. As I’ve posted before while I own a fozgometer I much prefer (and get better results from) aligning azimuth by ear using this method. 
http://www.durand-tonearms.com/Support/Support/azimuth.html