many connections advertise that they are \'faster\' while still pulling the same bandwith stream. the way they do this is to load old information (cookie and cache data) from the last time you visted that is stored on your computer right away, and then pull in any new information while your buisy looking at the version saved on your computer. The plus to this is an appearence of faster speed. The downside is that your looking at old information, and depending on the type of page, you may have to refresh like your saying.
To check it, go online without anything transfering, and then go to this site. see if you have data being transfered after the page is fully loaded. If there is, then this is most likely what is happening.