What are the Channel Addition modes AND and XOR used for?

What are the Channel Addition modes AND and XOR used for?

In the timing menu you have the capability of ANDing the even channels or XORing the odd channels. This feature (only available in slots A-D) extends the DTG's capability to create very unique timing patterns. With the combination of delaying one channel and using the Channel Addition functions the user can create patterns that would be unavailable otherwise.