Having had a think about it, it is quite a clever strategy. As they aren't standing in constituencies, the snp will still likely get half, or close to half of those, but by so doing, self-limit their potential to get list seats. So a second "serious" (?) independence party does have the potential to hoover up the list seats. It seems unfair that there could potentially be such a majority of MSPs supportive of a country-changing policy that only around half of voters support, but obviously, the "no" supporters have to split their constituency votes (as well as list votes) over more than one party, so can't run with a similar strategy. And that's not going to change.
But its success does rely on a really good info campaign on their part to explain the complexities. And I think that is where they could fail. I'm not sure they will manage to get the same people voting for both "NS" and "AS" given the way the independence community has divided into one of two camps.
Also, DH suggested Alba was an acronym. Alex's Loony Bampot Alliance maybe? 