Interesting discussion, which has I see reached the 4th page. I note that 4thpage mentions, at least twice, a commonly cited CBA virtue - ease of key transposition.
I read through it all somewhat hastily, but I didn't notice anyone chiming in, in support of that, until the 3rd page - and there it's somewhat ambivalent, since that person describes a 3 row approach that uses the other rows and thus apparently might really be a 5 row approach.
What I'm talking about here: the transposition feature requires that when you learn the passage that is to be transposed, you play it exclusively on 3 adjacent rows. As mentioned earlier, traditional players do indeed tend to play on the outer 3 rows. Now this might be easier for some passages than others, but as we can see from their example, it's sure possible to play in this manner with incredible facility.
As usual with my musical instruments, I puzzled out a way to do it on my own, and didn't trouble myself to adopt any traditional method for playing C griff CBA, and I use all four of the rows I have. I would really have to discourage that for others, as I belatedly realized that it smacks into a cognitive weakness of mine - when I am confronted by two different ways to do something, it takes me at least twice as long to do it. But it does make it a little easier on the fingers in places.
Anyway, I invite the CBA players to comment on how significant an advantage they really feel it is, that 5 rows hands you transposition on a plate.