Letting readers reply without an account I don't control

## Spark

Digest, week of 2026-08-08: #515 asks how a reader replies to a post without a
silo account. It landed the same week the footer's Bluesky link was found
pointing at a handle that no longer resolves (#508), and the same week webmention
lookups were fixed to match the canonical trailing-slash URL (#517 → #518).

## Why it could be interesting

The activity is "I set up syndication." The claim is that POSSE is only half a
loop: syndication solves *reach* — getting the post in front of willing readers
— but every reply path it creates runs through an account the reader must hold
and I must keep alive. The dead Bluesky handle is the proof: the outbound side
kept working while the inbound side had been broken for long enough that nobody
mentioned it.

If reach rather than audience-building is the north star, the interesting
question is whether a reply surface is *required* at all, or whether the honest
answer for a personal blog is that replies belong wherever the reader already
is, and my job ends at making webmentions resolve correctly. That's a decision
with a real cost either way, and #515 hasn't picked yet.

## Open questions

- [ ] Settle #515 first — the decision *is* the post, and drafting before it
resolves means arguing both sides.
- [ ] What actually breaks for a reader with no silo account today? Walk the
path end to end rather than asserting it's broken.
- [ ] Does Bridgy's Threads support (#514) change the calculus, or is
backfeeding into webmention.io still gated on a platform decision I don't
control — the same dependency the post is complaining about?
- [ ] Is the dead-handle incident a lead or a footnote? It's the concrete detail,
but it risks making the post about link rot instead of reply surfaces.
- [ ] How does the full-body RSS change (#267 → #497) fit — is "the whole post
travels to the reader" part of the same reach argument?

## Source material

- alunduil/blog.alunduil.com#515 — decide how readers reply to a post without a silo account (the open decision)
- alunduil/blog.alunduil.com#508, #516 — footer Bluesky link points at a handle that no longer resolves
- alunduil/blog.alunduil.com#517 (opened and closed this window) → #518 — webmention lookups match the canonical trailing-slash URL
- alunduil/blog.alunduil.com#514 — Threads engagement backfeeds to webmention.io via upstream Bridgy support
- alunduil/blog.alunduil.com#267 (closed) → #497 — RSS items carry the full post body as content:encoded
- alunduil/blog.alunduil.com#502 — every dlvr.it route on rss.xml prefers summary content
- alunduil/blog.alunduil.com#77 (closed), #520 — Bluesky autosyndication; release-feed syndication documented
- Adjacent existing idea: #289