Lately, I have increasingly seen this behavior on the main site: some users, especially high reputation ones, posts pseudo-answers as comments on questions.
Is this something that we want, as a community?
Let's avoid that, please.
Besides that, it's painful for the asker. On some questions I asked, I have had dozens of comments containing attempted answers. Did that answer my question in any way? Not only it did not, but also makes the community seem effectively dismissive, hostile and insular.
Think about that, your off-hand comment is going to sound either obvious and stupid ("Isn't the answer obvious?"), or witty but hostile ("What a stupid question").
Let's use the site features in the way they are most effective:
PS: You are not seriously trying to avoid downvotes, right? =)
It depends and I say that mostly because someone could have enough to write up a quick comment with a possible source (e.g. "I don't think that's the case because I seem to recall seeing [source] that said otherwise.") but not enough time to write up a formal and well sourced answer and the circle back around when they have more time to write up an answer, or someone else can work off the comment to be able to write up a formal answer.
In general, they aren't something we should encourage or want to keep around though.
I often have no time to do thorough research, or only have a few old written sources (or museum artifacts) as reference material, which are not acceptable (maybe they should be, there's more information that's not online but might be found if someone went looking for it in a dusty old library than there is online and it's often more accurate, especially for older things).
Posting that as an answer only gets a spade of downvotes and deleted posts, so I tend to post it as a comment to the question (or to an answer that might benefit from the additional information) for others to use as a basis for their own research.
Disallowing that would weaken the site.