I'm working on a sample script that calls out to the User Profile service and retrieves some sample data. I noticed that when I deploy the Application page and render it, I get a considerable gap between the last web resource being loaded and then my calls being made (got it clocked in at .5s). The screenshot below shows after the result being called a few times in a row, so I have much lower exeuction times for the POST calls, but I still can't figure out why they just don't start after the last Web Resource is loaded. If anyone has a starting point on how to figure this out it would be a huge help. We also notice these gaps on pages where we're using Content Search Web Parts, so I think it's something to do with our server setup.

executeOrDelayUntilScriptLoadedcause a timing gap? I will try Chrome, but I'm not so familiar with it's debugging tools.