I've not been able to find a resolution to this issue. It's been going on for a few years and I've just dealt with it, since at least SP and InfoView 2010.
We now have InfoPath 2013 and I've built a new account request form that pulls and submits to different SharePoint 2013 lists. The form works, okay, but when it is being filled out it just seems to keep rendering. Which makes it jump and flicker. Also, if a user checks a box before the form 'settles down', then they must keep an eye on it to be sure it took. Typically, they'll have to check it again. Same with clicking on buttons. The user has to wait until the form is done doing what it is doing, then select a button. The buttons, in fact, even keep rendering - getting smaller, before finally settling on their correct size.
I've already removed postbacks from everything I can find. When filtering drop downs, I'm using separate data connections with different sort by criteria. I did have my data connections being queried at the time a 'continue' button is pressed, but that still didn't help the flickering problem. So I've now got all data connections being brought in on form open. My thought process was, it may take a little bit longer for the form to load, but then it wouldn't flicker and jump whenever a user attempted to select items.
Unfortunately, this was not the case, as it still flickers and jumps. Has anyone seen this? It happens, most noticeably, in IE. But also a bit in Chrome and FF. Our company standard, of course, is IE, so ideally I'd like to have it fixed for that browser (the latest version).
One of the suggestions I've found is to change to REST connections. When I do this, the form loads data okay when in InfoPath preview or InfoPath filler, but when published to SharePoint, I get the 5566 errors. I've already to a question in the Connections forum about that.
http://www.infopathdev.com/forums/t/31849.aspx
Hopefully, I can find a solution. Right now, I'm going back to the drawing board and creating several separate forms to accomplish the same thing this one, more robust, form should do.
Thank you, in advance!
~ l