You're reading the wrong number. N=10 for IM.This study had a sample of 3 for IM. Not statistically relevant at all. Plus ask most of the users here. When they double or halved their dosages if their TT doubled and halved as well. It is not linear.
What any one individual reports on a forum is at best unreliable. And surely you've seen the study on large inter-injection measurement variations. I hope you're not proposing that we just tabulate what people on the Internet tell you and call it science.