I’ve taken this into account, and my idea is to sum all sends of the same asset/address and just do one send. This would be implementation-wise. Validation-wise an address/asset tuple with a cardinality > 1 would invalidate the MPMA send. Will clarify in the cip.
This is a bad idea imho. Bitcoin doesn’t limits how much i can use the same address in one send, why should we? Otoh, adding duplicate entries in the address-LUT table is a bad idea, would make 2 different versions of the same message valid consensus wise and make undeterministic what LUT index is picked for each asset/address send.
This is done already, a send of 0 invalidates the MPMA message, will clarify in the CIP.
Doesn’t makes sense. Adding an additional LUT will just be a wasteful use of space, as assets need only to be specified once per send. In fact, i will outline in the cip that specifying the same asset more than once would make the message invalid (for two reasons, spam/waste and making the message not determinist).
For MCAT asset groupings make sense too, the idea here just to include a way to specify source address (which i have an idea for)