Like in most fighting games with supers, KOF XIII pauses the game during the startup flash of a DM. During a super flash, only the player who caused a flash can input commands until the freeze period wears off. This allows the player using a DM to buffer a MAX Cancel, but it poses an issue for the defending player.
When on the receiving end of a DM, all directional inputs are consumed and all previous motion buffers will be eaten. This means it's impossible to buffer a counter DM inside of the opponent's super freeze time. Instead, the player would have to immediately input their counter command just after the freeze expires and also before the DM connects. Depending on how fast the opponent's DM is, blocking or rolling may be the only realistic options. Also remember than invulnerable and armored EX moves can usually be inputted faster than DMs.
In the rare instance that both players input a DM within one frame of each other, each player will start their DMs one after the other, much like when quickly sending a super back at the opponent in most fighting games.
Though this is incredibly rare to ever see in a real match, if both players activate a DM on the exact same frame then both supers will start up in real-time with no freeze time. This causes DMs to behave differently in terms of speed and invuln lengths.
When a Neo Max is activated, the game timer will stop until the attack hits or misses. If a Neo Max is activated on the last second of the clock and connects into a long animation, the opponent will take the full force of its damage before the round will end.
Hyper Drive Stall
A select few DMs pause the slow drain on the Hyper Drive Mode bar. This makes it easier to MAX Cancel a select few longer DMs.