You're saying that frost is not as good because it depends on rng fof procs ~20%. Then you say fire is more sustained but it also depends on rng crit, which DOES scale with gear. And dps significantly scales with gear. You can go look at simcrafts ( which I'm not fond of ) but. If in heroic gear you are doing 12-15k~ dps. And in full raid epics you should be around 20-23k, then there is calling. And gear does change things significantly.
This thread is getting silly. It comes down to RNG in all honesty. And while spec a may bemore or less rng than spec b. they are both still rng dependent on a fight to fight basis. As you mentioned, one run x dps, the next y dps. This holds true for fire as well, as getting no crits will yield bad dps.