Take a look at the video. Looks like there is an adjustable spring on the back for varying levels of flex. It also looks like it uses the Dalbello/Full Tilt tounge design.
It is not an exact tounge, but looks like one from the same design theory.
and might i ask where you buy your "anti-ankle breaking" boots?
as for the forward lean question... the whole point of the thing in the back is that you can adjust your forward lean from standing straight up to leaning WAY too fucking far forward... you have options
Hate to be a buzzkill here, but these are NOT NEW boots. These are old Raichle Snowboarding hardboots that were then made into ski boots by Raichle, then turned into freestyle boots by LINE, with the LINE Transfer (blue boots, circa 2000). Amplid has just tweaked the buckles on this version, but they definitely aren't inventing a new boot.
Link to a pair of the old Raichle boots on ebay:
its not a tounge design, its just the placement of one of the buckles, it locks the heel into the heelcup alot better. which is good on a boot like that with the capability to have a real soft flex.
id like to see them in person
Line did Full Tilt