I made a Gnome Artificer light repeating x-bow build expecting to end up with a 15-20 critical threat range after taking the final weapon training enhancement with the Improved Critical feat. Instead, it ended up 16-20. I thought it would be 15-20 because that is what my swashbuckling Bard is after it's +1 enhancement. It must be applied before the Improved Critical feat on the Bard enhancement and after it on the Gnome. Any idea if this is WAI?