If Renown had been lost to her dry-dock machinery fire, what would Britain have built to replace her in 1927?
Short answerThe likely replacement would be an F3-derived fast capital ship, using the treaty replacement allowance and the Royal Navy's continuing need for speed.
NotesThe counterfactual assumes that an accidental loss could be replaced within the available treaty tonnage. Britain would still want a fast capital ship, making a variant of F3 the preferred candidate. F2 with six 16-inch guns is another possibility. F3 receives preference because the 15-inch/50-caliber gun proposal would still be close enough to revive in 1927.