I’ve been following this thread and noting some similarities between Join workouts and CTS/Strava, FasCat, and Velocious. Three years ago I ended up using a FasCat off-the-shelf plan, increased volume average to 6.5 hours/week from previous two years of 5 hours/week, and was surprised that ‘easier intervals’ and a little more volume resulted in more performance (FTP and other metrics).
Since then I hired a FasCat coach, and he made intervals ‘easier’ (for lack of a better term, apologies for not being more precise) and we increased volume to 8 hours/week in 2022 and FTP and overall performance keeps increasing.
In the 2022 year in review thread I posted the graphic that clearly shows my response to volume/consistency:
Rather than minimum effective dose, I think of it as a tradeoff between increasing weekly hours while keeping the ability to recover and absorb the training. Everyone is different, what works for me may not be enough stimulus for your unique ability (and life situation) to recovery and absorb the training.