"Colin W Kingsbury" wrote:
Pray enlighten me to one thing- let's say I'm on V123 and cleared direct to
FUBAR which is defined by the intersection of V456 and V789. Leaving out the
legal-vs-practical debate, there is no way for me to navigate from my
present position to FUBAR in a straight line sans RNAV.

Sure there is. Get a position fix (VOR-VOR radial cross, VOR-DME, DME-DME,
NDB-NDB bearing cross, GPS, Loran, Omega, Celestial, whatever). Plot that
fix on a chart, measure the bearing from your current position to your
destination, adjust for estimated wind, and fly the heading indicated.
Take additional fixes along the way to correct your heading as required.

It takes a bit of work (possibly more work that is practical single-pilot
IFR in a typical GA cockpit), but it's certainly possible. Depending on
what equipment you've got, there may well be better methods than what I've
described. Knowing how to do it is the difference between being a
navigator and being a button pusher.

Like Colin, I'm going to bypass the legality question completely, but
there's no doubt that it's possible to do.