I've just written the following comment:
-1because I have always found the "I suspect that..." format troubling when used in Stack Exchange answer posts. We always encourage users to source their answers. If everyone started posting guesses in answer posts following the lead of the site moderator, we'd be in big trouble.
and I'd like to see how others feel about this to see if this view is shared by others or if the community has divergent views on this.
Searching my user name for "I suspect" in quotes returns 13 posts; 11 questions and two answer posts. Checking those two answer posts once can see that they are both heavily sourced and my suspicion is ancillary rather than central to the answer.
Searching the other user's ID for "I suspect in quotes returns 89 posts, almost all answers! There are way too many check how many are well-sourced and how many (if any) are 100% suspicion-based answers, but I suspect there are at least a few.
Question: Are "I suspect..." answers okay? What if we all started writing answers based on authoritative-sounding and reasonable suspicion?
I suspect there are dozens if not hundreds of users here capable of users here able to write likely-to-be-correct or correct-sounding "I suspect" answers, but I suspect that most of us restrain ourselves from doing so because we believe that SE answers in science-based sites should always strive to source their facts so that readers can verify and read further. I suspect that up votes have a popularity component so they can not be 100% relied-upon.