Hi

> My guess is the user was using a client that does not adjust TX fee, and
> needed to manually set it in order to get the TX in the block sooner,
> and meant 15 mBTC or something.
> 
> I suggest that either :
> 
> A) TX fee may not be larger than sum of outputs
> B) TX fee per byte may not be larger than 4X largest fee per byte in
> previous block

I don't think a such "feature" or lets say protection should be part of
the consensus layer.

Such checks should be done by the tx creation clients (wallets) – or –
nodes could have an option to not accept transaction with insane fees
into their mempool (policy).

</jonas>