Continued:
So we'll assume Best still gets ousted and Starr remains in the group.
Very little will change in their music for some time, I think.
Chas will probably not sing, but Lennon and McCartney will be heralded as the new Holy Grail triple threat of harmonizing, composing, guitar virtuosos.
In TTL I see them getting even bigger.
With a slightly more blues bent on their first record I could see stuff coming out of the Crawdaddy Club getting a bit bigger a bit sooner...
Now for the Clapton bit:
We'll say Paul McCartney leaves the band in roughly 1966 or so when the group stops touring. Maybe John and Paul have a worse relationship because they step on one another's toes more TTL.
Paul leaves and Chas Newby quits music.
John Lennon hires the dream team of Eric Clapton and Jack Bruce to usher in the heavy blues/rock/power pop/psychedelic movement with him and Starr (they were looking for a group at this team, and the group became Cream).
The Beatles continues on as a half Beatles/half Cream hybrid.
McCartney becomes something of a solo artist, and he calls upon Klaus Voorman from the Hamburg days to be his bassist, maybe also inviting Pete Best (or even more interesting: Ginger Baker?) to be the drummer.
The songs won't be OTL, but if you take all of McCartney's songs from this period and make it one group - then take all the Lennon songs from the other group and add a hint of Cream you have a pretty close scenario to the sounds you wanted above.
And great rock music on both sides, methinks.
ADDENDUM:
Here's another interesting thing perhaps.
Say Harrison does pretty well for himself in other local groups and one of them gets asked (as several did OTL) to move down to London to play the circuit. One of the biggest misses of OTL was that the Merseybeat couldn't have spread into the blues clubs of London, essentially mixing Beatle and Rolling Stone sounds before the British Invasion took off...
So here, why not have Harrison's group bring Merseybeat to the Crawdaddy Club in the late fifties early sixties.
When the Starr, Lennon, McCartney, Newby Beatles take off in say 1961 or 62 (earlier, you see, than OTL) have Harrison bring Best and Voorman (who he may have met in tours of Hamburg after the Beatles opened the door) to start his own Bluesbeat group.
They get big, just under the levels of Beatles and Stones success, but they don't do a whole lot until Paul McCarntey joins up with them in 1966.
So in 1966 we have the Beatles: Lennon, Bruce, Clapton, and Starr
And the other band: McCartney, Voorman, Harrison, and Best.
The rest is history.
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