That hasn’t been my experience and I’m certainly no spring chicken. 
I followed a XATA phased progression (Base-Build-Peak) for 4+ months with these results.
Continuous ATP is essentially floating in Build phase with suggested HIT workouts at or around your selected Focus Type when form is fresh/blue. Or endurance level (easy to moderate) when form is yellow/tired. Or rest/recovery when red/v. tired. TL increases or decreases at the ramp rate you control.