Scummer, -55 TSB is a real big number with a 50 CTL. I think many people believe you are risking injury/sickness by increasing your training load that much, that quickly. My CTL is about the same, maybe higher but it's showing too low as it doesn't count my crosstraining week+ of skiing (which shows as zero) so all my numbers are understated, the CTL the most. My CTL was at 40 before I left for skiing, dropped to 28 while I was out there, and is only now back up to 48.
For those who are unfamiliar with the numbers, the usage, and the benefits, they are more than significant. I don't believe there is a pro rider in the world who doesn't keep strong track of and manage his training according to similar numbers. If you properly taper for a key event, it can increase your performance by more than 20%. There's old school (or uninformed), and you get 20% slower. You choose.
http://www.sportvelo.com/tips/taper.htm