[Question] Does anyone know...

If there is a difference between the way hydro roots and soil roots grow?

I have a buddy that puts his cuttlings in what looks like your regular humidity dome but instead theres a huge base filled with water... he lets the roots grow till there about 6-7 feet tall and then plants them striaght into 5 gallons of soil and gets about a foot of growth within 48 hours? My description is probably off horribly but anyone know of the idea?

I wouldn't think they would "grow" any different. It's just the fact that when they grow in soil they are growing to hold them selves from the wind, and also to "search" for water. On the other hand hydro is also holding itself from the wind but it's already in water at least most the time so it just takes in nutes. So its just the fact on how rich your soil is and all the other factors that play in with hydro and soil. So saying that, means its all on how you grow the plant not what your growing it in.