Yeah I have had several problems working with .svg in illustrator, the biggest one being wacky arbatray resizing of the document bounds when I try to open and edit an .svg. I was forced to export off a master .ai file rather than re-edit native .svg, a pain in the arse!

The workaround I use is opening the .svg in a text editor and editing the properties manually, you can clear out a bunch of adobe auto generated garbage and get the file nice and small.