I realise their standard probably doesn't include all, but it seems like the obvious choice. Maybe I've just been conditioned by autotools, but I think it's standard practice to have all be your default target.
As long as running `make` does the Right Thing, does it matter if it does it via an `all` target or by defaulting to a different first target?
I do agree that generally `all` is a common convention, though.
I usually structure my targets so that I can run `make test` immediately without having to know what all the random commands are to build/install.