Zhai Sheng did not merely hear about this incident, but he even had photos.
Zhai Sheng was caught off-guard by the photos that Peng Yu showed him that he almost fell for his trap.
If one was slightly distracted during the military drill, one could easily cause the entire regiment to be wiped out by the enemy. If so, it would be a shame on them.
Peng Yu was very ambitious. He wanted to prove that he was better than Zhai Sheng. The military drill was a good chance for Zhai Sheng to suffer a crushing defeat and for him to have a definite win over him.
Therefore, as soon as Peng Yu had the photos, he had been planning for Zhai Sheng to suffer a crushing defeat.
Peng Yu had almost succeeded.