Looking at the plans, which are really blocks and not plans IMO, they are structured as harder and shorter intervals on Tuesdays (VO2 nomenclature but probably not really VO2 - different topic) and longer threshold work at 100%, 102% culminating at 104% on Friday (HV) or Saturday (MV). I’m not seeing 4x16 min at 106% workouts in the polarized plans but may have missed it.
Putting aside for the moment if these are good “polarized” blocks to incorporate into a longer training program, I don’t see any workout or progression that is obviously over the top. The 4 x 16 at 104% with 7 min recoveries is a definite challenge. But as the final hard workout of the block, that is OK.
TL;DR For riders looking for productive plans with two hard days a week, the 6 and 8 week MV Polarized plans are not too bad to my eye.
A longer discussion:
If we start talking about polarized season planning and progressions, I think there is a lot more that TR could do here. I think the Polarized MV structure, with hard Tuesday and hard Saturday is a good start.
Where I would diverge is:
Step 1 – Perform a separate VO2 block (3-4 weeks) with multiple VO2 workouts per week using the principles EC has put forward. Follow that with recovery (2 weeks). This assumes some level of fitness of course. Starting cold into this type of programming is a bad idea.
Step 2 - Would be multiple 6-8 week blocks with the Tues/Sat structure but focused on threshold and extension of TTE. More LT1 work and specific SST/ FTP work on the hard days. As opposed to one not really VO2 and one pretty hard threshold or super threshold day. I would keep doing that sort of programming until I stopped improving. LT1 and FTP work is great stuff when incorporating TTE extension principles.
Step 3 - A race specific block if a rider is focused on a big A event. For someone looking at building long term fitness, perhaps something “fun” like a short duration power block or even a break from structured training doing the kinds of rides you enjoy for a couple months.
Step 4 for the A-event is a taper and race.
Repeat the macro-cycle as you like if it’s working.
Would love for TR to build some longer plans like that. Problem is this approach doesn’t fit well into the canned plan approach and it it is better for non-time crunched riders who also don’t need gamification to stay motivated. Which is not to say one approach is better than another. Just different.