MISINFORMATION??????
I am just having a very hard time believing a deisel powered anything stalked a carrier batallion without being detected.
When running on diesel engines, they are not so quiet.
It is highly unlikely that the "shadowed" our carrier strike group...they would be too slow to keep up, and if they tried, they would be too noisy.
We publish, in peace time, many of the whereabouts of our carrier strike groups. Particularly the Kitty Hawk. My guess is that the Chinese simply went to a point in transit and waited, letting our escorts pass by while submerged on battery power, and then surfaced at the closest approach of the carrier...or something like that.
I a war time footing, operating under a buttoned up condition and taking evasive action in transit, not publishing either the location, destination, or schedule...such a diesel electric would not be able to do this...particularly as our helos searched forward, starboard and port for any potential submarine interlopers.
OTOH, we have been foolish in retiring things like the S-3 Viking aircraft and their ASW capibility from our carriers. They had both the range and the endurance to range far and wide around the carrier prosecuting submarines (it is what they were designed to do). The helos are much shorter range. Leaves a hole and a vulnerability that an enemy will exploit if they can.