I went through school in the early 80's, though I began electronics as a
hobby in the 60's while in grammar school.  I have never thought of
current flow as anything other than positive to negative, and I never
have any problem with that.  In fact, most data sheets and app notes are
written that way now.

Of course, I learned before I was 10 years old that current flow was
actually electrons flowing, and that since they had a negative charge,
they actually flowed from - to +, but what difference does that make?
Only if you are interested in boiling them off the filament does it
really matter.

As for "holes", they are really missing electrons, and they can only move
when electrons come from somewhere to fill them.  A hole moving to the
left is really being filled by an electron coming from the right.

Neither electrons nor holes move at the speed of light, on average.  They
may move that fast when they move (I can't remember any more), but they
move in little bits, then they sit there a while before moving again.
However, hole mobility is actually worse than electron mobility.  That's
why P-channel FET's have higher resistances than N-channel FET's.  In a
P-channel, the conductive 'channel' is doped so that it has holes, while
an N-channel is doped to have excess electrons.  What travels at the
speed of light is the electric field which causes the electrons to flow.

All this happens at the quantum level, and while electrons themselves
have inertia, there is no inertia of electon flow (as there is inertia of
water flow in a pipe).  The thing that looks like inertia is inductance,
and inductance is caused by magnetic fields interacting with the
electrons, not by the momentum of the electrons.  It is the inductance
that causes the spark when you disconnect the paper clip from the
battery.

As far as Vss, Vdd, Vcc, Vee - they do come from the terms source, drain,
collector, emitter, which do refer to electron and hole flow, but I could
never remember whether they collected from the base, emitted to the
circuit, drained the channel or drained the circuit.  Therefore, I simply
remember that drain and collector are positive for the more common
(n-channel or NPN) transistors, and reversed in the other ones (p-channel
or PNP).  Since virtually all IC's ever built use primarily NPN or
n-channel FET transistors, Vdd and Vcc are always positive, and Vss, Vee
are always negative.  CMOS IC's could have been different, but they used
the conventional Vdd positive and Vss negative.

Sorry for the long post, but there was a lot of poor information going
around, and that's one thing I have a hard time abiding.

Don