Sorry
MB but you won't get an argument out of me on this issue either. It's been said that modern air navigation technology go to a lot of trouble to emulate the 17th century. It's true that modern nav systems such as IRS and GNSS don't need a magnetic reference at all. They work in true and use a built-in algorithm to convert true to magnetic for the pilot's benefit.
But it's strictly a "comforter" that is intended to imply that the pilot has some measure of control over his (or her) destiny. Magnetic reference had its uses and, for GA, probably still does - at least until Regulators bite the bullet and adopt GNSS as the standard nav facility. Then, just plug it into your autopilot and happily fly the exact same track - maybe even a bit more precisely...?
IMHO, reliance on magnetic reference breeds further reliance when there is no longer a need for it. Sadly, there is currently no end in sight to this perceived dependence.
Looks like you'll have to come up with another topic for an argument...
