Well, reviewing the methods from the paper:
It seems like you would need some way to exclude some portion of the isolated range from having ions extracted from it, as is currently possible with our DIA isolation schemes.
Though, even more than DIA, I can imagine the need for these excluded "margins" to be asymmetric, because we really want to extract the entire isotope distribution, which currently means -1 DA to as many as +6 for a triply charged ion, but even assuming we only support +2 (our default - 3 ions - M, M+1, M+2) then we need 1 m/z on the left and 2 m/z on the right for a 3 m/z total of overlap to support full isolation of the ions we currently inspect, since the 0.5 m/z margins are meant only to keep the monoisotopic peak quantitatively isolated.
So, I think this means supporting new UI that allows setting of margins on SIM scans. I think this could be supported with just 2 new values: left margin and right margin.