Sparing structures nobody scored you on

In head and neck SIB plans the scored organs are usually parotids, cord and brainstem. The swallowing structures — pharyngeal constrictors, split into upper, middle and lower, and the glottic and supraglottic larynx — often appear in no objective at all.

Adding mean-dose objectives for the upper constrictor and supraglottic larynx, leaving every other objective unchanged, reduced their mean dose by 3.9 and 4.5 Gy respectively. V60 fell from 82% to 65% for the upper constrictor and 63% to 46% for the supraglottic larynx, with modelled grade 2–4 swallowing dysfunction down 9.2%.

Target coverage and parotid sparing were unchanged. The dose was going into those structures because nothing asked for it not to.

The general lesson, which is the reason this is a skill and not a protocol. Dose lands wherever no objective forbids it. Before the last optimization, look at the structures you never wrote an objective for and ask whether any of them matter. On a scored challenge this wins nothing directly — and a write-up that mentions it is teaching something the leaderboard cannot measure, which is most of the point of writing one.