Which are better?
Here is another thing the TR team has looked at. Summarised in 90 seconds or so.
I could tell you hundreds of stories like this from our data. It’s nice and feels valuable but it’s very easy to paint what ever picture you want to when you keep the data so generic like this. This is like a science study without any details. No scientific journal would ever publish info in this format. TR is excellent at marketing. If people trust this it’s fine, just feeling like you have a plan or a strategy you trust is valuable in itself.
I am not saying they are doing anything wrong. They did some analysis, came up with a pattern, they presented it. It’s just I have done a lot of this type of analysis and it is so easy to take many subsets of this “"100k users” boil it down to 5k of them to paint different pictures of what works. Not to mention the average or median does not make the rule.
Not trying to be a pesimist. Nothing wrong it’s just over under = threshold, there is no magic in a little over and a little under that is provable. Most people don’t even have an accurate FTP based on today’s lactate levels, so it’s most likely a little over and a little more over.
I’m not on Instagram and can’t get the link to work.
I would say on-offs vs longer VO2 intervals is probably at the marginal gains level, if someone is targeting VO2 improvement it is more important to do the work and which version you do is a lesser concern IMHO.
Personally, I’ve changed my perspective a bit on training. I’m moved from a viewpoint of “I’m a cyclist” to “I’m a normal guy who recreationally rides bikes”. It sounds really similar, but I find there’s a big difference in what that means.
I don’t really like VO2 max intervals so I’m not doing them 
I would rather do something fun.
Dave