Warren writes:

Okay Mr. Science. But the flavor isn't from the heat. It's from the
smoke produced by the incomplete combustion of the wood in the
charcoal -- something you don't have with gas which is more fully
combusted.

The definition of "charcoal" is wood that has been reduced to nearly
pure carbon (and a bit of non-combustible ash) by cooking off everything
else in the absence of oxygen (inside a "retort"). Nowadays this is
done in kilns, but in olden days they used to just bury a huge heap of
timber under a clay mound, and poke a few holes for just enough air for
just enough fire to heat the wood to a temperature to boil off
everything but the carbon in the cellulose. People in this old biz
("colliers") were good at knowing when the process was complete, so you
didn't waste any of the fuel when the charring was complete. Before
coke (essentially the same process applied to coal, yielding a
technically pure carbon sponge) was perfected as a carbon source, this
was how fuel to smelt iron was made, and why England and the US were
largely deforested, and why today they're reforested.

As such, being technically pure C, charcoal cannot produce "smoke" in
the flavoring sense, but only hot gases (CO2, CO) and soot (amorphous
carbon).

Commercial briquettes contain clay and wax binders to create the dense
lumps from wood waste, but that doesn't really change the chemistry (the
wax is about gone by the time the fire heats up).

You may be confusing the "smoke flavoring" that comes from burning (or
even just heating) ordinary hardwoods like hickory, which not previously
having been "charred", still contains a lot of potently aromatic resins
that boil off in the smoke and cause the "smoky" flavor. Those flavors
are *not present* in charcoal, which is, in itself, flavorless.

Of course, any heating of meat, such as with charcoal fire, changes the
flavors. For example, proteins denature, and sugar is produced by
pyrolyzation and in turn is carmelized, and the cooked flavors appear.
But these flavors are not sourced in the fuel (carbon in the form of
charcoal), which is merely a heat source.