I think there's a difference between postulating a hypothesis, and then testing it, which is what I believe you're referring to, versus going around advocating

I think there's a difference between postulating a hypothesis, and then testing it, which is what I believe you're referring to, versus going around advocating a particular position as being true and then "testing" it. When people are strong advocates of a particular position, they tend to find ways to design or process experimental data in ways that support that position. The ways in which bias can seep into the experiment are not always easy for outsiders to see. So it comes down to whether their "advancing this theory" went beyond what a reasonable scientist would do in postulating a hypothesis that needs testing.