Putin and Russia's motives notwithstanding I find myself still agreeing with their position - in the sense that it seems preferable over a strike of no actual effect to "prove a point".
Obviously, though, this happens to be Putin's opinion because it's more beneficial to Russia. No one should be under any illusions that Russia and Putin have no scruples with using military power with or without UNSC authorization when it suits them. Or, at "best" case, they might feel bad about it but they still do it.
Even so, the ethical basis for his argument being almost certainly bogus - the part where he appeals to legal authority and upholding legislation even if one doesn't like it - I can't really see any obvious flaws in the arguments themselves.
In short: Even though I have deep doubts about whether he actually thinks like this, I still think what he's saying is, at least, less wrong than thinking that any problem at this point would be solved by NATO strike in Syria.
It's mostly a case of
Carpe Diem for Russia, in my view, rather than any political brilliance on their part.
It's a pretty tragicomic thing to have to agree with the leader of one of the most opportunistic, unethical, politically repressed, economically distorted, thuggish, and corrupt nations* on the planet on a matter like this, but I think it's more the fact that the US and rest of the Western world has
completely screwed up the political and media handling of the Syrian crisis. It has led to this ridiculous situation with the "red line" of chemical weapons having crossed but without clear proof of whodunnit, and are now scrambling to either do some kind of strike because they said they would do that, or to find some way to back off with at least some dignity intact.
Since Russia had aligned themselves with Assad's regime since the beginning, they just took advantage of these political blunders made by others - the only thing Russia and Putin needed to do to "seize the day", so to speak, was to present themselves as the ones who are against increased violence on the area. It's just a case of good political analysis; I doubt they
planned for it...
Or maybe, just maybe, I'm unfairly biased against Russia due to geopolitical and historical reasons.

Regardless of what I think of Russia, however, I'm inclined to think that any solution that leads to secure disarmament of Syria's chemical weapons arsenal is a good thing regardless of what motivates it. 'Cause right now I see those stockpiles as a huge risk of destabilizing agent not only in the Middle-East but elsewhere in the world, if the really radical elements present in Syria happen to get a hold on them and smuggle them out of the country. Worst case scenario is that this has already happened.
*The US is also on this list on my books, for what it's worth. Also includes China, Iran, Israel, Venezuela, North Korea, Saudi-Arabia, most other Middle-Eastern countries, many African nations, and Vatican. For varying reasons.