Help! Blender potentially corrupting files!

Blender 2.63a, I’m collaborating on a project with some artists using lightwave and modo, and often we share elements back and forth (using .lwo, .obj, .dae formats).

I have now had the experience several times where I will attempt import, it will fail, and will corrupt the file I’ve been provided. Thank god for shadow copy, but this has made me utterly paranoid. Why are import scripts given any write permissions??

Obviously best practice is to make a duplicate of any file before attempting to import, but this is still disappointing behaviour from the software.