Yes, it works, in the sense that it provides exactly what it says... a little more "support" when the derailleur wants to naturally twist that way. It doesn't change anything about your brazeon tab or your frame however. The little tabs are simply there to protect your frame from the screw going right into it. Many derailleur tabs have an appropriate spot that the screw will butt up against and making the stick on tabs redundant. But if your entire frametube/brazeon is flexing, the derailleur will move right along with it, as will the support screw.
And see that last image at the bottom of the page you posted above... especially where they say to set it up initially with a 0.5-1mm inward angle, then to use the support screw to push it out so that it's parallel with the chain ring. Be very careful with that guideline as I think it's way too much. Rather, I would try to get the cage set as parallel as possible with the chain rings from the get go, and only then turn the support screw so that it barely touches the support plate or brazeon tab, but still has contact so it can do it's thing.
Here's an example of what happened with a 2012 Cannondale Evo brazeon tab, which was not designed to be used with the newer long arm front derailleurs and the new support screw...
Old design (pre 2013) on the left. You can see where the support bolt made contact, but due to both the angle it made contact with the tab and perhaps the weakness of the tab itself, when the new Shimano 9000 front derailleur was being installed, as in the instructions you posted above, that 0.5mm of necessary final adjustment was all it took to snap the tab and break it. The tab on the right is the updated beefier version and also includes a flat "shelf" that the support screw can butt up against. The key in that last instruction is to just "tentatively" tighten the derailleur at this position, so that it can still move a bit on the tab without taking the tab with it as that final adjustment of the support screw is made.