Last Christmas the incident was 90 years old and got a good coverage in German newspapers. Some bits I remember:

The two parties agreed not to shoot at each other after the event and not to mention it 'further up'. But that failed. On the one hand the neighbouring companies noticed something unusual and on the other hand, the German headquarter noticed one war statistics looked wrong:

This part of the front had much less than the expected number of dead and wounded (when I read that I imagined them phoning the British headquarter and inquiring what was wrong on their part...). The telltale sign, however, was the sharp decrease of ammunition used on that front. Within 14 days after the event, both sides replaced the respective companies by new forces and the war statistics were quickly within the expected range again. The German headquarter decided to be quiet about the reasons for the replacement.

Wolfgang