Ken,
That's the first thing I thought upon seeing the taurus for the first time; and, that bias is the reason I carry a 6-inch .454. Prior to the casull, I carried a super blackhawk, which has an overall length 2 inches longer than the casull (I consider overall length to be more important to handling ability than simple barrel length). I'll admit the blackhawk, with its larger, after-market rubber grips handled as easily as the shorter casull. However, the redhawk, which is only one more inch longer (3 inches longer than the casull) feels awkward to me, both while carrying it and in rapid deployment manuveurs.
You talk about 12-inch barrel tauruses--it is definately a different gun, but my 10-inch barrel BFR in .45-70 is a full 6 inches longer (oal) than the casull, and is about as hard to carry and deploy as would be a 20-pound ham.
I've practiced some with the Raging Bull and while it is somewhat more difficult to carry and to deploy, it is a bit more pleasant to shoot. (I do understand that 'pleasant' is not a word used to describe shooting the .454 casull.)
Recently I had a chance to shoot the S&W 500--10 times--in my view, it is no more punishing to shoot than the 6-inch casull. I could get used to it! I haven't handled it enough to get a feel of my ability to deploy it. Steve