I am skeptical because I don't know whether the information presented and sources are real, yes. I will have to do some research of my own. I have also never seen the jets in my area turn off their trails, and I have also seen the hot exhaust they give off up close, so I still believe they could be giving off contrails. I can't, however, say the same about regular planes. My skepticism is a mixture of validity of information presented and personal experience.