Not sure if this will help solve your problem or not, but here's what i know...
For some reason when i try to do a 'title' in premiere, and have it by itself (not on top of any other video, ie. just it with the default black background) then when I render the vid, the text is all fuzzy around the edges. I assume there is a simple reason for this, and also a simple solution, but i am too lazy to figure out what it is, so i found myself a little workaround. For when i want plain text (a title) by itself, i record a clip of plain blackness (an actual video file of plain black) and then i put that into the project, and the title on top of it. And when I do that and render it, the problem no longer exists. Although sometimes when using certain fades the problem can pop up breifly during the fade (before the fade finishes).
Sorry if this doesnt help ya, thats all i got. I hope also that its understandable. I'm not sure if there are many others here who still use premiere or not (i think i am one of the small few who uses premiere over vegas), perhaps someone else can help ya.