VT Overland was a rough, rough day. TSS estimated at 260 (HR only on my cross bike, TSS is from correlation with TRIMP). I started out feeling tired, and yeah I was overgeared, but I'm getting fed up with this weakness I have of really fading badly past an hour or so. During that first hour, I'm pretty good and able to ride fast. After that, I crack and % of FTP I can maintain drops dramatically. I assume that the remedy for this problem is to really up my base training over the winter, and that's the plan, but I'm a little paranoid that this is just some fundamental weakness I have that I can't fix.