Playing the banjo just like Earl Scruggs is a common effort among some banjoists. I even have one or two that I play almost exactly like him, but those are the exceptions, not the rule. This is a fairly natural pattern of thought. After all, for most beginners, it is the only reference point they have at first, thus the natural tendency to sound just like what they have heard.
As time progresses, and as you skill level goes up, don’t worry about getting the song exactly like the original version. Here’s why.
1 – It’s too much extra effort. If you’ve been playing very long, you already have your own style, which may or may not be similar to whoever you are trying to emulate (usually Earl). Although it’s true that playing someone else’s version will introduce you to new licks and techniques, you want to keep this in balance: not too much of totally new stuff, yet also not too much of totally your own creations. Strike a happy medium here. If you try to play totally someone else’s version, you will miss the advantage of the standard banjo licks you already know.
2 – Low ROI (Return On Investment – a financial term). What will be your reward for learning “Foggy Mountain Breakdown” exactly like Mr. Scruggs played it? Sure, no doubt it will sound pretty cool if you get it up to speed and it is played cleanly, and with the right accents in just the right places for his style. But that’s about it. The original was already done, the initial buzz from someone else playing that first version has come and gone.
3 – Nobody notices. Except for a few banjo players (and geeky ones at that!), no one is likely to ever notice you have played the song just like someone else.
4 – It impedes your own creativity. Similar to argument 2 above; although you will get some advantage from looking at how someone else did it, there are only so many standard licks you will get from one player. After learning a good number of others’ licks (external licks, you could call them), it is better to create you own, in your own style.