Thats really spooky - this morning I have been playing with some still life shots and (not having a remote release) have been experimenting with mirror lock and self timer, although as I started writing this post I realised I had introduced another variable - I was using a stablised lens so I have just been back a reshot with IS off.
I've used a 1/2 second shutter speed and my conclusing is that using self timer has huge impact in reducing unwanted vibrations on its own. Its also something that anyone using a non SLR camera can take advantage of.
I can't see any difference between the last two shots (w.o mirror lock & with) although as they were all saved with the same compression settings, and the last one is a slightly larger file I guess there must be slightly more detail
(I though the "Anti Shake" logo on my Minolta a fitting subject for this experiment
)