I knew everything I listed was mandatory, but what I was saying, is would you have to put them on the chain in a certain way? If not, then I don't see where Peten would miss his timing with
Delinquent Duo, in essense, the two cards are still being discarded by one single effect, just one right after the other.
It's like
Delinquent Duo with one card in your hand, that card being Peten. You can't tell me he'd miss the timing by him being the one randomly discarded, and then the second half of DD, you discard an invisible card that doesn't exist. That would just be plain stupid. I gotta go with novastar on this one until we hear something more concrete. Otherwise, everyone's going to need to play mandatory chains after DD has happened without the option of which of the two effects to pick first.
With
Night Assailant for instance, do you pick the Flip: card target as soon as it's discarded, or when it activates after the current chain ends. If you had to choose as soon as it's discarded, then you wouldn't be able to bring both
Night Assailants back if both were discarded by DD, because even though they're both mandatory, the first one "missed its timing" to target the second one, so it would have to choose another monster, or none at all.
I would even think, according to your logic, if one of those monsters were to be discarded first, that Peten would miss his timing if he were discarded second, because a new chain has already started, so you'd miss the timing there.
What about if all three were dumped via
Painful Choice? Can only one activate, while the other two must sit there and do nothing?
All I'm really saying is that DD is one single effect resolving, forcing multiple cards to go to the graveyard at once, one is just random, while the other is chosen. It's not two effects on a chain, it's just one. I think that's what novastar's saying as well.