I think the core idea of #7 is to give a vast amount of freedom to each person in their work so they can let their brain run wild on the problem without restriction. Even if that's not what PG meant, it certainly is what I mean.
I think the other great benefit is that each person can afford to become an expert in their areas, rather than each person becoming merely competent at everything. I think 3 people who are each experts at 3 different things is more powerful than 3 people who are merely competent at the same 9 things.
No problem with the idea of letting peoples' brains run wild on a problem. I suspect you and I could debate for some time about your latter point; I'd worry about things ranging from bus factors to developers who become expert in some set of things later being confined to those areas of expertise to avoid stretching their knowledge portfolio to thin, whatever that means. Maybe it is worthy of it's own conversation somewhere; maybe such a conversation already happened that I could get more insight from.
I think the other great benefit is that each person can afford to become an expert in their areas, rather than each person becoming merely competent at everything. I think 3 people who are each experts at 3 different things is more powerful than 3 people who are merely competent at the same 9 things.