That was in the 5th sentence at the beginning of a very long article. It was made as part of a preamble to the article. An article that was meant to satisfy the "distinct lack of solid information." It was not a conclusion of the article.
As a general observation, I find that scientists rarely use expensive tropical fish to test theories on what will kill them. Typically, they use inexpensive fish like guppies, goldfish, or even trout or catfish, so there is likely no study on how to kill off Aros by eliminating B1 in their diet. However, below the top of the article there was a lot of information about B1 diet deficiency with salmon.
http://www.thefishsite.com/fishnews/10639/wild-salmon-discovered-in-new-yorks-salmon-river
Here is an article about Salmon and what has happened to them due to having a diet that is now heavy in thiaminase. Of course, salmon aren't aros, so each owner has to decide if they want to test out that theory within their own tank or avoid thiaminase-laden meals for their fish.
There are studies on the internet about the effects of feeding foxes, rabbits, mice, and snakes diets that include thiaminase-laden fish. In humans, B1 deficiency is called beriberi.
