it's more than enough of a reason, what are you talking about? You think that playing at 85% of your potential is OK when Aff can play at 95% and Destro - at 99%.
Demo can never beat Aff in DPS, considering same gear & skill. Demo is designed to be a support DPS tree, like Arms. Sure, Demo (and Arms) can do competitive DPS, but it will never surpass Aff. Stacking haste & crit and acting like you're a Fire Mage (keeping up DoTs and using one main nuke and one proc) won't make you top DPS.
On Molten, Destro is the most working spec. The only bad bug it has is inaccurate pet scaling (a general class bug), which affects your overall output by very little - that's all.
I'm not saying you should avoid Demo. I'm just saying that if you're after DPS, you shouldn't think that Demo is the way to go, which is how currently 90% of the Warlocks think on Molten.
As for the guide - there is a better Demo guide out here instead of this wall of text. Not to mention the mistakes in it. I appreciate the effort, but it was a waste of time making it, sadly.
Urukago @ Ragnaros