Cannot disable rule in .csscomb w/o also disabling it in user settings

[ashtonsix]

I'm using csscomb on a project but don't want to use the rule space-after-selector-delimiter because the selectors are grouped based on length / semantic meaning like this (contrived example):

.message-error, .message-success,
.alert-error,   .alert-success {
    font-size: 16px;
}

Leaving the option out of .csscomb achieves this.. unless the rule was set in the user preferences in which case the project setting (ommited, do nothing) is overriden.

I should be able to set a rule to null or similar in .csscomb to prevent this behaviour