no key consistency mechanism and reuse of input circuit makes tagging possible

[nothingmuch]

if this used isolated circuits, then multiple info requests could be made to ensure consistency of the blind signing key and the round ID:

blindjoin/client/src/http.rs

Line 52 in 982fc28

let resp = self.alice_client

since this reuses the "alice" client identity instead of using isolated circuits for each info request a malicious coordinator can tag clients using distinct round ids or blind signing keys