Haha that's awesome man! I think Mike is the one that did the videos but it's kinda crazy to see how the building process we use has changed from the time he made those to now. Even when I first started working there about 7-8 months ago, we've revamped most of our process but our layups have always been the same. (Don't think I'm allowed to share how we do it but it's definitely not rocket science). My word for you is that if you are going to use the Rossi fill, make sure you inlay it a bit and don't leave it exposed. I had delam on my set because the water expands the material and the expoxy doesn't bind it as well when wet. A full legnth version of that fill however does sound very interesting. What I've noticed from pressing it is that it doesn't flatten any more than the thickness you get it in. It's about the thickness of three pieces of triax when pressed so maybe layering one underneath and one above would work? Although having different fills( tri, bi, etc.) all do different things to the ski. Building your own set is a trial and error process that takes time to refine and perfect so you may see yourself going through three or four pairs until you get to ones that preform how you like and won't explode from experimental building techniques.
I don't know if you checked out our website but we do workshops where we take you through every step of building a ski and if you wanted to experiment a bit during that, I'm sure we'd be open to it. (Idk how much our set price is for that tho) and we even are building workshops for people, businesses, and schools to teach more people the building process. I was talking with Mike the other day and he was saying that building skis is cool and all but what he really likes about all of this is the learning and teaching aspect. By making workshops and stuff, we are teaching more and more people every aspect of a ski and what parts of the building process lead to which outcome. Now, I talk a lot on these forums about skis (I'm sure you can just pop your head in a few threads and see my name) but being 16 I am able to learn what's going on in the industry right now and apply that to future years in my life. It's kinda my dream job to either start my own company or be hired by an existing one to design and test skis based on intended performance and by seeing trends happen from before my years and during, I can apply that to the future and probably create some mind boggling designs that will either turn out to be amazing or complete crap haha. Even in just my last 14 years of skiing I've seen people go from full camber everywhere to mass introduction of rocker in every type of ski.
Tl;dr I honestly don't know where im going with this tangent but building skis is about risk, trial, and error. Before even designing a ski, you need to look at your materials you want to build with and materials that have been built with and see if they will even work. After checking that and pressing your sticks, try and beat the everliving shit out of them and see where their weaknesses are. Then, modify, re-press, mount, and try again!
lol