Bad math. Alternative Vote (to give it its more common name) produces phonier majorities than first past the post. No system run on single-member constituencies can avoid phony majorities as can be seen in a simple example: 100 seats  are contested by 2 parties. One party wins 51 seats by a slim majority while the other wins 49 by a large margin. The first party won most of the seats but the second party got most of the votes.

Rather than accusing people who've done the research of being dishonest, why don't you do a little of you own? Look at the mess AV has made of Australia's House elections. Or look at what it did to Fiji (2 coups and a decade of military rule before they got rid of it).

Follow your own advice and stop spreading misinformation about a voting system that has been dropped by more nations than currently use it. And start explaining why nations that use proportional representation overwhelmingly move to make their systems even more proportional after using it.