Brian, it's obvious your not a true computer nerd, so let me explain the algorithm...

Before high powered computers were invented a 50 pound pack used to feel like 80 pounds, and that's before you even strapped it on and lugged it for a mile. That's 30 extra pounds you were carrying. Now that 80 pound pack that feels like 50 pounds is actually saving you 60 pounds, so when you only put 50 pounds in it you end up being 10 pounds lighter than if you were carrying nothing at all.

It takes a really big computer tower to figure this kind of stuff out, and that's why you also want to bring condoms when you get "The ultimate backpacking outfit". Computer nerd hiker chicks go crazy over a big package like that and there's a sub routine for a 3D simulation that shows that more often than not it takes both an axe AND a Bear Grylss knife to fend them off.

Honestly, with all the miles you've hiked I'm surprised you haven't seen that happen, all the computer simulations indicate it's very likely. All I can say is you really have to get indoors more