Funny Tungfa, you have/find some of the best pictures, LOL
Cryptonewb, if two instantX transactions are sent, and they go to two different masternodes, the first one that clears wins. If a block is found that includes the wrong one (because somehow it didn't get all the information), it is rejected. Maybe that's why we'll be forcing IX transactions to go to the second block now? So that rejects will be minimized?
Also, for reading up on the instamine, please go to these two links:
https://dashtalk.org/threads/the-birth-of-darkcoin.162/and
http://dashdot.io/alpha/?page_id=118