Nicads really don't require much more a 1/10c charge for 16 hours, or untill slightly warm, and go fly. the only real reason for cycling is to check cond. I suspect your introducing some error into the eqation by manually having to switch between charge and discharge as well as using a peak charger. Nicads are not considered completely discharged untill .8v so it sounds like your battery is just fine. The best insurance is a loaded volt meter before each flight. Stop flying if it drops below 4.8v or 6V depending if your running a 4 or 5 cell pack. For added insurance, batteries should be changed out every 2-3 years or monitored more closely. I personnally don't let my batteries get to old and use a loaded volt meter and never had a failure, (knock on wood). I never fast charge either.