...To justify the price increase...
Man, the scrapper4 is a deal and a half. It will likely hit $199 on the secondary market the day they ship... as was the case with the INFI-Coot.
generall, as you harden metal, it becomes more brittle and prone to chip/shatter, and less likely to bend/deform. One must generally compromise, as you want maximum hardness (edge retention and general tuffness to distroy whatever you are working on) without taking catastrophic damage to the blade (chip/shatter). Too soft and the blade will wear quickly and not hold its edge,.. too hard and your at chip risk.. simple right..
INFI is able to reach superior hardness while not approaching brittle/chip risk and staying 'soft' enough to bend rather than chip... a bend or roll can be sharpened/smothed back, a chip is metal lost and does not come back..
INFI is especially well suited for large blades, which are generally made at low hardness as a catastrophic break (as in, in-half) is very likely wiht a brittle blade... in this case, INFI offers superior hardness, again without the brittle risks...
In a small knife, the benifit of INFI is smaller, but you still get an easy to sharpen knife, of superior toughness, and if you pry on it... she is less likely to shatter and send your hands into your work, and into your pieces of blade...