Ken, you're right, this is absolutely not a sport bike, and really nothing other than a sport bike can compare to one, except maybe a sport tourer that leans more toward sport than tourer. I will say though that of all the heavy cruisers I've owned, from a Shadow 1100 to a VTX1300 to a VTX1800 to a Thunderbird 1600, the CTX is easily the best handling. I might even go as far as to say it's better than the 3rd Gen Magna 750, though I must admit I didn't own that one long enough to really thrash it properly to make a fair comparison.
Chris, I still think that it's the extra weight that you're sensing. It's simple physics -- the harder you push the bike around, the more that weight is going to reveal itself. It's why sport and racing bike manufacturers go through great pains to eliminate every unnecessary ounce of weight possible -- less weight equals less affect of inertia, which equals greater flickability. The CTX is a great handling bike for its size and weight, but there will inevitably come a point where two little contact patches will be overcome by around 900 lbs of bike and rider, and that point will be much sooner than with 700 lbs or less.