If you click on this google page, you will find, at the bottom, a stratfor's article with the title:

Turkmenistan: The Battle to Follow Turkmenbashi's Death

It's interesting, I think.

Hello Greko,

Yes, the Stratfor article is very interesting:
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This means that all eyes should be on Moscow and Tehran for the next few months. For the past two years, the geopolitical strategies of these two countries -- to tie down the Americans -- have been relatively in sync. But now there is a prize that both desperately want, and one that cannot be easily shared. With former Russian spies being poisoned in London and militants raging in Iraq, the world should know full well that these powers do not play softly when the stakes are high.
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If Iran invaded this country and shutoff the pipelines running North, it would put the kibosh to Russia's European export power, and simultaneously strengthen Iran's ability to twist the arms of any Europeans who support Iranian nuclear sanctions.  For a very small military outlay, Iran can suddenly become a true energy lynchpin; a formidable natgas superpower.  I think Iran would jump at this chance, then seek to broker this natgas to China and other Asian countries.  The Iranians would only have to hold this ground for a very short time as a proxy force until the Chinese Army marched in overland thru Dushanbe, Tajikistan.  Will we see American and NATO forces coming to Russia's side to prevent the Iran-China hookup?

Bob Shaw in Phx,Az  Are Humans Smarter than Yeast?

Or perhaps Russia threatens Iran with full sanctions if Iran messes around in Turkmenistan.
With the US and Israel just itching for an excuse to attack Iran, I find it hard picturing the Iranians being stupid enough to get on the bad side of Russia at this critical time by making a play for Turkmenistan gas.  Russia is the only powerful country in the area that is anywhere close to be an ally of Iran.
Along with Bob, I doubt that Iran would play a heavy and transparent game--i.e., a direct invasion.  Too many would jump at the chance to punish Iran.  Even if Iran could grab Turkmenistan, all hell would break lose at home: Expect both the West and others to trumpet Iran's attempt at hegemony in the Middle East and its nuclear ambitions.  Bombing Iran would occur in short order--easy and painful.

On the other hand, better to control by proxy this valuable piece of real estate.  In short, a few more assassinations, control of the next ruling madman--you all know the drill.