From personal experience I do know that specific people not only review your data but actually run your program and look at your UI. I had a misconception about my app and was asked how it functioned.
I am also working through an issue where I used a UIWebView on the flipside of my app.
Here is a screenshot of what they were reviewing at the time. The last communication I had was this:
Hi [developer],
Your application, Geopher Lite, cannot be posted to the App Store because it violates section 3.3.5 of the iPhone SDK Agreement; "Applications must comply with the Human Interface Guidelines and other Documentation provided by Apple."
Geopher Lite duplicates the functionality of the built-in iPhone application Safari without providing sufficient differentiation or added functionality, which will lead to user confusion. The app should launch Safari when the "Go!" and "Log" buttons are selected, instead of navigating within the app.
...
Should be an interesting conversation, assuming they even reply.
If that's the case, what good is the UIWebView? You can only do 6 functions with it as-is.... forward, back, stop, reload, goto URL (admittedly a file or web page) and handle some javascript in the pane. Just doesn't make sense.
Sorry, rant off, it's a bit off-topic. =)