The "regime" has never denied having chemical weapons, to the contrary. If you want to know more about Alloush and his connection to the events, I suggest you click on the link I provided instead of cutting it out of your quote of my post.
btw, the terrorist was banned from twitter finally after some serious efforts.
I followed your link and saw a lot more links but nothing actually to refute the reasoning in this post
Lots of sources, there are other assessments too - Thanks to ApolloGnomon for the Brown Moses blog link, which is pretty authoritative.
Possessing the weapons is only one part of conducting such an operation.
We know that at least some came from what look like rockets, and some have been bent as if on impact. This blog (which I linked to earlier) lists a lot of evidence about this - it is a collation of the publicly available information and description of it.
Thursday's post shows videos of UN inspectors linking the projectiles to the attack
As well as that, the actual operation needs to be carried out.
Given the fact that several areas were hit at the same time all surrounding Damascus, would require a large scale use of weapons with detailed planning in order to do this.
They would need to devote a lot of scarce resources to this attack on their own area rather than defending their neighbourhoods, and those involved would have to hide their involvement from their comrades in the weeks prior to the incident without anyone having second thoughts and warning their friends. The risk of such a plan being exposed would also end the rebellion, and it would be almost impossible to keep secret.
Look at the little things that annoy thread to see how well humans are at project management - the more complex the more chances of failure. Everything would need to work like clockwork and be implemented by chaotic organisations, whilst under attack and having diverted massive resources away from the actual role of defence without any one noticing.
A rebel false-flag attack would violate the rules of project management. It would be impossible to pull off without going wrongorand getting discovered, and such an attack would end that part of the rebellion which organised it.
ETA: In other words, the people who ask what the regime would have to gain from the attack being attributed to the regime haven't asked what the rebels would have to lose from a false-flag operation being discovered.
Immediately the attack helped the regime tactically.
If it was a false flag operation, it was one that caused significant harm to the rebels and helped the regime.
Elsewhere a poster commented that the situation in Syria with Assad and ISIS is like choosing between Mussolini and Pol Pot.