True story: a friend of mine literally transcribed about 30-40 of the songs from that book into Sibelius and learnt all the guitar parts (!) Then he and another friend did backing vocals and he played bass (he had to teach himself too! He has more respect for my playing now

) Then they were trying to get gigs as a Beatles cover band, and no-one would book them because they "sounded too good" and one guy actually accused them of sounding like there were more than just two of them and a backing-track "no-one could do that!".
So sometimes it's a better idea just to be a lone wolf! I have that book and it's helpful with some of the parts that's hard to hear with the rest of the instruments. But be wary, the scores still get things wrong!