unsetting input format options

So we have a base installer which defines an input format for wysiwyg with a bunch of settings for showing buttons and such. Something like:

input-formats[wysiwyg][wysiwyg][settings][buttons][default][indent] = 1

However, in our sub-profile, if I'd like to tell this one to not be set, I thought i could simply do thus:

input-formats[wysiwyg][wysiwyg][settings][buttons][default][indent] = 0

When I go to the UI for this (admin/settings/wysiwyg/profile/4/edit) the option is unchecked, yay!

However, when I go to an input form that has a textarea with this input format selected, all of the buttons that I had setup in the parent installer still show up.

If I save the options in the UI which, as I said, correctly reflect the subprofile's unsets, the textarea's wysiwyg is now correct. I'm suspecting an operation order is out of whack here or something.