It takes a lot of work to learn someone's style. If they play a lick involving 1-3-4 fingers, and each note is even, yet you have trouble with your pinky and ring finger separation, your cover of anything involving that is going to sound different. To get it right, you have to find an exercise to use, and spend however much time it takes to make those types of sections even.
Just how fast your natural vibrato "shake" is, can be very different to one you're trying to emulate. The writer of that solo didn't "work on it"; he just played it the way it came out of his hands. See: Paul Kossoff, Ace Frehley, etc.
And players like Jimmy Page..., very hard to cop their style, because of the..., erratic nature of their playing style.
Assuming you really know how Jimmy sounds, just pull up any number of covers of The Rover for example, and see how many totally miss the mark. Too choppy, (staccato-like), not sliding into notes, not overlapping notes where Pagey did, extra note noises, too much distortion (just listen to how clean the solo actually is)..., all sorts of nuances that become the difference btw just playing the song, and nailing it.
There's even a "wrong chord" that the first time I caught it, then played it at rehearsal, and someone heard it and pointed it out to me, and I had to show it to them on the record. (maybe that's going to far, but hey, I wanted to nail it.) Right before the vocals come back in. Page slid down too far and hit an Bb instead of B for the 5th.
