Exactly. A basic rule I learned in creative writing classes is that you have to provide enough context for the readers to understand what you are trying to tell. Expecting readers to be familiar with material vaguely reminds me of how
Gerry Conway's criticism of Batman V Superman: Dawn of Justice. Although it's a
very different subject, I do think that there are some points he make that could be adopted to this conversation. For example, he said "A good writer does not depend on details external to the current narrative to justify character behavior." While this applies to justifying Batman's behavior in the movie, it reminds me of Mets's claim that Slott assumes readers are familiar enough with material that he doesn't need to explain things, expecting readers to connect the same dots, but in Slott's case, he's relying on details external to his own current narrative. Even if it's part of a continued history, when you have something like Darkest Hours, the explanation that Mary Jane could "sense" Peter was only available on the previous version of this forum, before being added in Darkest Hours itself. You
do need certain explanations. Knowing that the Jackal uses clones explains how he keeps surviving (Even if it's a lazy copy of "It was just a Doombot"), but why should we accept the lack of explanations for Mysterio's return or Daniel dressing as Roderick? Just because other writers provided explanations does not mean Slott doesn't need to provide his own explanations.