The scenario deliberately places the clash in 1926, before carrier forces are numerous and mature enough to accompany every operation. Carriers would more plausibly be concentrated for major fleet actions and reconnaissance than attached routinely to a fast raid. That leaves room for new battleships to attempt an unsupported dash against Singapore. The premise is deliberately constrained and does not imply that battleships operated without scouting or support in every circumstance. A real Japanese commander would probably reverse course immediately after sighting the larger British battle fleet.
Notable Point · 32:29-33:11
A 1926 raid before carriers dominate
The 1926 setting makes an unsupported fast-battleship raid more plausible because carriers are not yet available in large numbers.