Well yeah, there's no accounting for RNG shenanigans. I have failed four 99% chances in gathering before, oh ho trust me I know!

But it doesn't have to be consistent. Even that huge burst at the start is more than the other healers can bring, and extra Balances are just icing. And the other cards help besides. WHM has some nice new skills though, which is probably the only thing keeping it from becoming AST/AST. The SCH scorn is wholly deserved, however.