Combustion heat does not split water.
It turns it into steam.
The steam then dampens peak combustion temperatures - I use this feature daily at work
- which will help in reducing NOx.
Introducing more Nitrogen (in the amines), and claiming that it'll convert to N2 instead of adding NOx during combustion is also more than a wee bit weird given that plain N2 will turn into NOx when the temp is right..