Could a reinforced Royal Navy contest Japan in the Far East?

Is it too optimistic to think British carriers could threaten Japan at night or adapt tactics well enough in an alternate Far East war?

No: the Royal Navy possessed unusual night-carrier training and substantial Mediterranean experience, and Italian neutrality could free enough additional forces to make a stronger British Far East defense plausible, although not certain.

Japan's intact carrier force would still have had a night-fighting weakness: the Fleet Air Arm had invested heavily in night takeoffs and strikes, while Japanese carrier aviation lacked comparable training and radar-directed night defense. That specialist capability was costly and dangerous to train, but it reflected a Royal Navy determination to correct perceived night-fighting failures after Jutland. Operation C nearly produced a British strike after the Royal Navy detected the Japanese fleet, so the opportunity was more than theoretical. Years of British carrier air defense against Italian and German land-based aircraft also challenge the assumption that only Americans could adapt air-combat tactics. The Thach Weave was one effective solution rather than the only possible defense, and Mediterranean combat had already forced British forces to evolve their own methods. If Italy remained neutral, ships and submarines historically absorbed by the Mediterranean could reinforce the Far East, making a British success plausible enough that Washington would have strong reasons not to remain aloof from a Japanese war.