Sounds like a bunch of malarkey - how old is that post?
My guess is that it was written before RSG was officially released a year ago and perhaps one had to install token-blessing. Nowadays (since fw 7? everyone is on 7.2 - 7.5 now) RSG is openly available to the unwashed masses.
Note what was said is also wrong on refering to RSG as "exposing the DOM of screen representation" - that is not the case, it does not apply to the screens from SDK1 (roScreen, roImageCanvas and ro... everything else except roSgScreen). Rather, RSG (aka SDK2) is a new - and by magnitude harder - way to write UI for Roku. You don't use RSG as automation hooks for the programs - rather you write in it. Start with Scene Graph XML Guide
and Scene Graph XML Tutorial
if you want to learn RSG - just consider yourself warned wrapping your head around it won't be easy.