A DPS Simulator

[pandabearcat]

It's not so much DOT overwriting: it's when you are attempting to overwrite a buffed DOT with an unbuffed DOT. To be specific, the FF14 game actually tells you that your DOT didn't take effect.

I see what you're saying, the message output of the simulation logger does actually tell you "Cannot Overwrite!" as a warning, but it has no effect on how the engine handles the action.

To be specific the engine handles the rules, just the rules. Anything not explicitly illegal will be allowed. Very few metrics (just tp and total potency) are stored, as well as gamestate.
The message log handles the output of messages (if turned on).
The events store the damage, crit, buffs, etc, and by default the logger will output those as well.