Wayne, I was going to correct myself to state that AC is aware of the delay in Closing a chart, but their release notes indeed say Opening a chart.
Personally I am aware of both delays but the resounding nag here seems to be of the closing delay. Our experience is also 2-5 seconds to close, but enabling the removal of deleted items at log out shaved about a second for those who were OK with it. Opening takes about 2-3 seconds.
I hope they are working on a fix for the delay in Closing a chart to resolve the accidental exit of AC.