NO it isn't. Steam north into bad weather and rough seas for "training"? Planes and pilots are expensive (as were torpedoes..., and we know where that led); why add to the risk of losses? In your eagerness to get some US CV's wrecked you are postulating the rediculous. There is one rational "what if" that puts a US CV in Kido Butai's sights..., and that is if the Enterprise Group hadn't been held up a day and had sailed into Pearl on the evening of the 6th. The rest is just "pie-in-the-sky" fanboyism. Like my suggestion of KB wrecking a couple of CV's on French Frigate Shoals through a night navigation error. That's silly..., but so is your "let's say a US CV was screwing around 500 miles north of Oahu for no understandable reason".
Respectfully, sir, it is not "ridiculuous" assumption that the Americans would excercise north of Hawaii.
https://txspace.tamu.edu/bitstream/1969 ... -Wadle.pdf
In Grand Joint Excercise 4 (GJE40), in February 1932, Lex and Sara operated both north and south of Oahu to "attack" Pearl Harbor. (Described on page 80 of the above PDF.)
Later that year, Fleet Problem XIII, units based in Pearl were to attack the US West Coast. The opposing fleets engaged in the waters far north, and eventually east, of Hawaii.
In Phase 2 of Fleet Problem XIX, March of 1938, Saratoga repeats the PH attack, from a point 100 miles north of Oahu. (Phase 1 involved a carrier battle around the Hawaiian waters between Lex and Sara. Phase 3 involved Sara and Lex operating versus "enemy" bases in the Sab Fran area, but again maneuvering out of the shipping lanes north north-east of Hawaii, attempting to avoid detection.)
The USN was not as timid in getting their ships banged up as you seem to indicate.