How open is the Strait of Hormuz?

We know one thing for sure about the MoU that the US and Iran have signed.

The US wants the Strait of Hormuz opened as quickly and fully as possible. If that happens, oil prices keep falling for a while and governments get a chance to replenish their strategic reserves. To keep oil flowing at the maximum rate in the 60 day negotiation period is what the US wants. 

At the end of 60 days, there is room for an extension. The US administration will keep talking so that oil prices are under control in the run up to the mid-term elections to the US Congress in November. 

Iran would like oil to flow as slowly as possible. The greater the pain to the global economy, the greater is Iran's leverage. Moreover, within the 60 day period Iran cannot charge tolls or fees. After 60 days, it feels it has the right to charge fees towards services rendered to the ships.

So the incentives for both sides are clear enough.

What is not clear is how far the Strait has opened. The priority is to get the estimated 1000 ships stranded during the conflict out at the earliest. The sailors on these ships have had a terrible time in the past 100 days. The middle portion of the Strait needs to be demined and that will take time. Ships can pass through routes close to Oman or those close to Iran. 

The International Maritime Organisation (IMO) has created a route close to Oman through which, they say, tankers stranded during the conflict are passing at a furious pace. Iran objects, saying all ships must pass only through its own designated routes.

Just how much is going through?

In normal times, 135 ships transit the Strait each day. Military analyst Larry Johnson provides data to show that on June 23, only 7-13 ships transited the Strait. On June 24, according to FT, an estimated 41 ships transited, 15 via the Iran route and 26 via the Oman route. That is a huge jump. 

And that jump is precisely what provoked the Iran missile attack yesterday on a ship using the Oman route. The IMO has since suspended its evacuation plan. So the Strait appears to be closed again for practical purposes. 

In return for opening the Hormuz, Iran gets some of its assets released and it gets a waiver of oil sanctions for 60 days. But it loses it leverage over the global economy and the US economy.  

The ceasefire period thus seems to be working to the advantage of the US. The Oman route is spoiling the show for Iran. Iran cannot allow a situation in which it does not control the flow of traffic in the Strait of Hormuz. Hence the Iranian attack on a tanker in the Oman area.  

Will the US construe that as a violation of the MoU? And how will it react if it does?