Gidday guys.I have a question for the more techy guys here- it's about the common ignition advance mod.

I've just modded the ignition plate on my GS500 '05 E model,but now i'm confused if it's actually done anything.....
The main reason i'm confused is that i have been checking the timing with a timing light,but there seems to be no change no matter what angle the backing plate!It always shows the 'F' mark pointing at the trigger module tab.
Am i measuring it wrong?perhaps the mistake i'm making is that the F mark will naturally always line up because thats what it does.Perhaps i've advanced it correctly but i've just measured it wrong,haha
However,some say that these late model bikes compensate for any changes,making it all pointless.Is this true?That would imply the bike measures the timing elsewhere.

Anyways- details of what ive done so far-

My bike should be the normal version with 12 deg advance at idle so i advanced it 5 degrees- which turns out to be 3mm of counterclockwise rotation measured at the mounting screws.It was pretty simple elongating the mounting holes that much.
Does this sound right so far?