That sir, might not be a fact.
I just got curious and just ran some simulations with coach parrot.
Two players with skills all at 1, 6'0".
First player goes with a regime which trains his DR to have 6 points above OD, then train OD for 1 pop, and continue for 1 more pop. So throughout the entire regime, the player's DR and OD difference will be 5-6 levels.
Second player goes DR all the way to 20, and then OD all the way.
Based on the first training regime, to hit DR 20, his OD would have to reach 14. To achieve this point, if that kid started training today as a 18 year old (season 61 week 12), he would hit the point at season 69, week 9.
If we train DR all the way, he would hit 20 DR at season 68 week 4. At season 69 week 9, his OD is just 11. So that's 3 whole levels slower. He will only hit 14 OD on Season 70 week 8, which is almost 1 full season slower.
To make things more interesting, I adjusted the trainer level to 7 (by default coach parrot uses level 4). Your regime only hits that mark at season 69 week 1, while the first regime reaches that mark at Season 68 week 4. So even though the gap is smaller, it is still a good 11 weeks slower.
I don't know what other sources you have which can objectively back up your claims, but feel free to share them.