240 committed himself to an opinion on the avionics of interest which should have triggered off interesting and informative exchange of ideas such that a common understanding of the navigation systems could be reached - what should have been a starting point years ago.
Gentlemen, the silence is deafening - don't be shy of putting your understanding forward, some systems are hard to grasp and you, as aircrew, needed to use them well, not build/fix/tweek them. One of my ex's had a favourite saying when I went into unecessary detail on, say, a car fault - "Tell me the time - not how the clock works!".
Problem is in this case, to understand their options, we do need to understand the nav systems.