Cliff çburton and his ''string spacing''

[SSCBA]

Hi, I was having a look at cliff's basses and I found that he used basses with tighter string spacing than standard (specially the Aria Pro II) I don't know what's the spacing of the alembic, but I think the RIC had a tighter spacing too.
Why?? it makes easier to play the kind of solos that Cliff played?

[jsbass]

Easier so he could rake with his fingers.