on my question, Question for Military Experts. That's fine. Keep the question in mind. If you run into a military resource which bears on a Turkish-Syrian conflict per my hypothetical, please post it.

TZ is running a Turkish geopolitical analysis of "Who's on First" in the Middle East, ‘Ankara is Iran's rival whether it likes it or not’ (8 Mar 2012):

Turkey and Iran are two countries in the region that have not been paralyzed by the events of the Arab Spring. “I believe that Iran, the oldest imperial regime of the region, will try to preserve its position in the region at all costs,” Çağaptay added.

While Turkey turned its back on the East and tilted toward the West, Iran strengthened its hand in the region, Çağaptay noted. But when Turkey refocused its foreign policy on the Middle East 10 years ago and began deepening its relations with other countries in the region, Ankara became Iran's rival.

“If the Arab Spring had never occurred, there would have been secret competition,” Çağaptay posited.

He pointed to the two countries' conflicting stances on the regime crisis in Syria, which he said has taken the Turkish-Iranian rivalry to an unprecedented level. “While Turkey supports the Syrian opposition, Iran has decided to support Syria's Assad regime. In the end, either the Syrian opposition or the Assad regime will win. In other words, either Turkey or Iran will win.”
This article leads me to a second question for military experts (the first one - a Turkish-Syrian 1 on 1 - is still on the table):

If Turkey were to proceed with a conventional armed intervention into Syria, and Iran responds with a conventional armed attack on Turkey - a 2 on 1 with full commitment of military forces by all three states, who would win ?

No US-NATO support of any kind for the Turks; and Russia and China stay out of it completely (other than making noises about "aggressive war", etc.).
The Turkish preference (based on what TZ and its columnists have been saying for the last few months) appears to be a Turkish-brokered diplomatic deal involving Turkey, Iran and the Arab League (Saudi and the Gulf states as the money partners) being the "peacekeepers" and guarantors of limited negotiated external interests (Russia-China; US-NATO) - a reverse Sykes-Picot, in effect.

Regards

Mike