Hi Mincehead,
I would disagree with the word 'tricked' as there is no deception...i.e you are not bypassing anything. As mentioned in my thread on here - the parameters (set by the manufacturer are not altered in any way, shape or form)
The tuning module and ECU both work hand in hand together.
Have a read of this - I'm sure you've probably already read it anyway...
http://www.volvoforums.org.uk/showthread.php?t=138720
Hopefully this will answer any other questions you may have,
Thanks,
James