That would depend on how good/successful you were with your "old" methods. You can have the LS system showing cover & fish like it's a dang laptop, but you still gotta present your lures to them like "they" want.
I've seen a lot of fish hanging around my jigs on my LS/93sv, but don't always feel the thump & sometimes I don't even know they have it in their mouths until I raise the rod tip. Sometimes a little jiggle with the rod tip will bring them screaming in towards the jig, and sometimes it'll send them dashing for cover. Sometimes a color or size change (up or down) will get them chewing, sometimes nothing you do interests them.
I don't have Livescope to "outfish" my old methods, but to complement them & add to them. Just because I have the LS doesn't mean I'll stop casting, Pushing, or any other method I want to use. To me it just means I won't be slinging jigs to every piece of cover I know of, or find .... unless the screen tells me there's fish on that cover.
But to answer your question ... it don't take "hours", more like months !! But then, how long does it take to perfect those "old methods" you mentioned ??