Although whether psycholinguistics is on- or off-topic is an important question to ask, it is a separate question from whether a particular question that happens to fall in the domain of psycholinguistics is on- or off-topic.
It's like if I'm participating in a scavenger hunt where the goal is to obtain some food item containing chocolate, and I know that a lot of people make chili using chocolate, I can't just walk into a restaurant and order a bowl of chili and expect it to fulfill the requirements of the scavenger hunt without knowing its ingredients.
I think one reason your question about reading scrambled words caused so much controversy is that it was a giant bowl of chili and some people weren't convinced that it was made with chocolate! Simply mentioning the word psycholinguistic (as in, "Is psycholinguistic research done on this topic?") didn't make it an incontrovertibly on-topic question because so much of the rest of the question was concerned with reading and how our eyes and brains process printed words with spaces between them. Usually if you ask a linguist about language perception, she will assume you are talking about aural perception (unless you are talking about sign language). By wording the main question the way you did, linking printed words and sentences (not the central concern of linguists) to pictures (also not the central concern of linguists), you all but bypassed the facet of this reading phenomenon that is relevant for linguistic research! (By the way, morphemes are not printed entities, although some orthographies use units that correspond to morphemes. English orthography is not one of them.)
I'm still new to this site myself, so I'd be interested to hear feedback from people in the form of comments, but it seems to me that rather than getting flagged as off-topic the reading question could be salvaged by being reworded. For example, a linguist might ask, "What role do morpheme boundaries play in the phenomenon described above?" or "How language-dependent is this phenomenon? Do languages whose orthographies demarcate word boundaries with spaces fare better than other languages in this regard?" or "Has any typological research been done on this phenomenon? Is there a correlation between ease of reading scrambled words and where on the synthetic-isolating scale a language falls?" The two answers provided (to date) for the question as it was originally worded actually speak more directly to these other versions of the question, bringing it more into the realm of linguistics.