I've just noticed that the size of any .fla file never gets smaller, only bigger...?

I'm working on a flash site, and have many varations of the same fla files. Trying diff tunes and graphic stuff. It appears that if I am, say, trying a bunch of diff tune files, and import them all at the same time so I can run thru them, the resulting fla size was 11 megs. After stripping out all but 1 of the tunes and some graphics, the fla is exactly the same 11 meg size.

I've checked this against a bunch of diff flas and it appears to hold true? odd.

oh, and the resulting swf file is only 69k so its not a big deal unless you want to post the fla file somewhere...

Me