Hi Frank,
Yes, there are many reasons to follow a Base plan twice in a row. I often recommend following all or a portion of the plan at 50% volume the first time around, then at 100% volume the second time around. This is a great way to ease back into Base training after a long break or injury.
If you can follow the plan 100% the first time, it is likely you will get more performance gains from following a Build, Peak and Race plan such as our Category 1 Cross Country Mountain Bike Build, Peak and Race Mountain Bike Training Plan or Masters 40+ Cross Country Mountain Bike Build Peak and Race Mountain Bike Training Plan, than a repeat of the Base plan.
Coach Lynda