While the difference in implementation between these two training:recovery schedules is obvious, what is less obvious (to me) is the difference in terms of progression and outcome.
In what scenarios and for what reason(s) is one better than the other?
Thanks.
It mainly depends on your overall fitness, ability to recover and experience with training. A more experienced cyclist will opt for the 3:1 program while the 2:1 program is more suitable to less experienced athletes.
There isn’t a clear tangible criteria to define which is best for you.
Basically it is related to physical ability.
In an ideal training plan we must push 100% and beyond when required, in order to improve, but if we are tired we are not able to do it.
For some 3:1 is too hard and 2:1 is better.
For some others, the opposite.
I guess the old version of the plans give an indication; 2:1 was applied to the novice and intermediate level plans, whereas 3:1 was only applied to the Advanced plans.
Thus it will be level of fitness, experience, age/ability to recover, etc. that decides whether one or the other should be applied.
… adding to that, progress will most likely be faster for the 3:1 ratio, but basically sets higher requirements to physical ability, as mentioned by @azrogm
Perfect, got it, thanks!
= 3:1 probably preferable, unless you find you are unable to recover enough to give the hard sessions your all, in which case 2:1 might give better results.
If you think that fits your physical ability and level of experience, I’d say go for it! If you’re in doubt, I’d say start with the 2:1.
Just to add to this, there is also an age component - the older one gets the more recovery one needs so 2:1 may in fact land up giving a better outcome than a 3:1 where an athlete is getting insufficient recovery time. I’v seen somewhere the age of 55 as being one to consider 2:1 plans but I would imagine that’s highly variable.
Agreed, that is why i wrote
in my first post 
Thanks - missed that. Perhaps it’s time for me to go to 2:1 
Naah, you just need to cool down and wipe the blood off your eyes, and you should be good to go 
And if you’re female, 3:1 for all plan volumes is a godsend. Now most of us can train roughly to our hormone cycle no matter our fitness level!
They cover the 2:1 vs. 3:1 in this article here, just to provide some guidelines.
If you’re like me, you sign up for a 2:1 plan, then on the third week you find all these cool new workouts (like the new On Location and Pro Rides) that you want to do, so you do them instead of your recovery week workouts, and then find that after 3 weeks of intense workouts you now have 2 more weeks of intense workouts… Then after 9 weeks you oversleep your alarm 3 days in a row because you’re completely blown to bits and end up taking 3 weeks to recovery and shove all the ice cream and donuts you can possibly fit into your mouth. Then you get back on the bike, ride Recharger… and the cycle starts all over again.