Dark_Azelf...calm...:P
What we're trying to say is that by a stall standard its defenses are not going to cut it, it's as simple as that. On that scale, it IS frail (though in general it isn't).
As for your claim that it's good on stall teams, I see where you're coming from as it can counter so much, but I would disagree. It dies to SO much and can't stall, it's practically counterintuitive. I like Starmie on about every team but a stall team. You could say it's personal preference and all, but on every stall team I've put it on, it has seemed really out of place. Maybe it's just me, but Starmie has been total suckage on stall teams for me.
Also keep in mind Tentacruel, Forretress, Donphan, or even Blastoise can fit into stall teams very easily and spin and do a fair share of countering things. Actually, Blastoise can beat Mixape and if you alter its set and EVs, Gyarados and Garchomp as well.
But yeah, we'll have to wait until darkknight responds...
EDIT: And he did while I was posting this. How about that.
And about Forretress, I can tell you it's awesome for stall teams. I run a Forretress on almost every stall team I make, 3rd or 4th generation.