I was reading this github gist about rbf improvements written by glozow. I had difficulty understanding parts of it. The main confusion I have is for this paragraph:
BIP125#2 can be bypassed by creating intermediary transactions to be replaced together. Anyone can simply split a 1-input 1-output transaction off from the replacement transaction, then broadcast the transaction as is. This can always be done, and quite cheaply. More details in this comment.
The BIP125#2 is:
The replacement transaction may only include an unconfirmed input if that input was included in one of the original transactions. (An unconfirmed input spends an output from a currently-unconfirmed transaction.)
Which from what I deduce, it basically means that a replacement transaction can only have one input of an unconfirmed transaction output. Is my understanding correct?
I also have taken a look on the comment glozow mentioned in the gist, but that doesn't helped me understanding how is it possible for one to bypass the restriction. Can someone explain it in simple language to me?
Thanks in advance