Two front war anyone?
Is it even possible to coordinate with Iran?
We can co-ordinate with Iran without collaborating. Divide areas of responsibilities and future spoils of war and operate within that. Pakistan army's doctrine in the event of an Indian invasion is to rush back into Afghanistan, which they've cultivated for strategic depth. India doesn't have logistics lines in Afghanistan to sustain our army there. Iran has direct land access to Afghanistan. If they move into Afghanistan to preempt Pakistan's recession into Afghanistan and deny strategic depth to Pakistani army, India can finish the job inside Pakistan.
Neither Iran nor India will want to be caught in a situation where both armies are congregated inside Pakistan while their army tactfully recedes into Afghanistan and nukes both of us inside Pakistan. The primary means to prevent Pakistan from pulling out the nukes is to make it known to them that they are trapped within Pakistan. Due to direct connectivity with the mainland, we have secure supply lines within India for the refueling and resupply of our columns in Sindh, under the full cover of AD. Similarly Iran has that edge inside Afghanistan and Baluchistan.
Just a passing thought : Israel tries to opportunistically burn Iran's fingers in every battlefront the latter is involved in and Israel also benefits from selling weapons to India. Per realpolitik, Israel's interests lie in the survival of Pakistan for causing attrition to Iran and for benefiting from weapon sales to India. No matter what Israel's twitter statements say, India must deliver a stern message to them no to meddle on this front to impede Iran when they move into Afghanistan. They will not stop the war, but they will try to prolong it in the hope that Iran loses a lot of blood and gets tied down here, to release pressure on Israel in the middle east, and hope that India would place an order for weapons on Israeli Flipkart as our ammo depletes. Israeli fanboi Swamy keep's expressing frustration whenever India doesn't go all out in the support of Israel. Swamy has his own agenda, the nation has its own interests. The Palestine card is a pressure tactic this is why we never surrendered all our bargaining chips in the name of friendship, be it UPA or NDA. People from the birthplace of Chanakya must not fall for the Baniya-giri of the Jew. No one is a permanent friend in international relations.