Keeping the oil fields out of unfriendly hands is just good strategy.
Anyone following the scene might perceive that Russia has steadily replaced Iran as Syria's major backer and influence.
Iran's interests in Syria via Hezbollah - having gained much battle experience - are now pulling back toward Lebanon border, some areas around Damascus ( probably for logistics), probably supporting shia tribal villages and militias, and maintaining a forward presence of Iran vs Israel.
It seems Russia is pretty much overseeing the Syrian military and have meshed themselves with the Syrians to negotiate on the ground, divide the opposition militias and negotiate with them tribe by tribe. Except al Nusra- aka Al Qaeda. Russia is as committed to their destruction as we said we were to ISIS.
Russia has an important mission to be deep,into Syrian command and control to prevent or delegitamize a future false flag chem warfare incident that will be blamed on Assad...and now Putin. This is what the US and NATO or “ other” anti- Russian operators will be attempting to set up as an excuse to escalate US military attacks on Syria - and Russia.
Its insane
If your "strategy" is to prolong the fighting, widen the conflict and drag the US into another regional war maybe... otherwise it looks like more globalist intervention that the American people are sick and tired of.