Nice catch.  I must be getting old....  

Throwing in my experience here, you are definitely not a kitty cat.  With my prior motocross experience, I thought I'd be able to ride on my new GS for as many miles as I could pay for gas to burn.  Not true at all.  My first few rides were just around town, but then I got adventurous and rode 50 miles one way.  Right at the 50 mile mark my bum started to ache really bad, and I was done for the day, but of course I had to suffer through 50 miles more.  Shifting positions didn't help, nothing really did.  Now I've got 7K miles on 'er, and recently rode from south western San Diego to LA, then rode with other GSTwin'ers through the Angeles Forest for a few hours, breaking for brunch, then riding north to Visalia.  All told, it is 315 miles from where I started in San Diego to my house in Visalia, plus the spirited riding I did in Angeles, and going out west to the I5 from the Angeles Crest.  I'd guess I put on about 450 miles that day, starting at 6:30 AM going until 4:30, almost constant riding.

Then, there was the day I put on 600 on my dad's YZF600R going from Chino, CA to central LA, then down south to Long Beach, from there heading up Highway 1 all the way to Pismo Beach, then over to Visalia via Highway 41.

THAT was a ride, especially after working on a farm for 3.5 hrs and then starting off on the ride!

Didn't mean to hi-jack the thread if it leads to that, just thought I'd share my experience with tolerance to miles.  It DOES get better, especially if you add bars that you like, and footpegs if you need 'em like my 6'5 frame does.