Im new, am a 3D designer. Need a New cnc machine and need advice and guidance

[JAZZCNC]

Suppose one leaps CW and the other CCW, both equally valid. The gantry is now out of square. You can bump every home switch in Christendom but the most you can do is detect the error, you can't fix it unless you can drive the motors independently.

Yes agreed but you obviously have no experience of how twin axis slaving works with home switches. They do move the motors independant so I'll say it again "It doesn't make a Jot of difference if you use home switches" Your argument only works if you don't use home switches and when slaving motors you should always use home switches.
Now to clear the Geek fear manual you have, which is unfair to geeks really, i'd call them fucking idiots my self then I'll clarify by saying "Separate home switches on Slaved axis motors"