When inserting html code into a page, block, blog, etc. there are currently three options for the input format: "filtered html", "php code" and "full html". The full html still automatically inserts pagebreaks based on linebreaks in the input text. This is very useful, however if you are inserting an html code that has linebreaks in it it can cause problems as it will put in pagebreaks where they are not desired, I ran across this when inserting a google adsense searchbar and I didn't realize why I had this huge space after the searchbar no matter what I did so I had to go through and make it so every line of the code was technically on the same line..
Inserting a fourth option for "true html" that would not include automatic pagebreaks would be useful for working with code that is not meant to simply appear as article text. (hope I explained this clearly, please ask for clarification if necessary)