well all I have to counter this well thought out post is the simple response of: A wizard did it.i've been thinking that azeroth must have a small density.
why i think that... consider those facts below, what do u think?
-you fall from great altitudes and dont die,
u can even fall from 3 storeys high and not loose any health.
-look at the weapon's and how we hold them; they are disproportionally gigantic
and we hold them horizontally to the ground as if they're made of plastic.
-same goes for fighting while wearing those huuuge shoulderpads.
-watch the zepelins; they lift an entire boat with just a same size balloon.
that is physically impossible, since its not magic.
-if you notice the ropes on the horde ship in icecrown they are bent.
meaning, the ship is lighter than the balloons. (that, i cant explain! i guess its magic O_o?)
-cyrocopters fly with those laughable rotors.
-the skybreaker in icecrown, a huge ship covered in metal and
filled with ammunition and soldiers, flying with just 3 tiny rotors.
-look at those wyverns/gryphons/hippogryphs,
they have those heavy bodies and those small wings compaired to their size,
yet they fly, and with passengers. (their arse must be able to fly on its own btw.
(cant explain how those things fly leveled! bio-enchant^^)