I refuse to be required to make the changes suggested in your "system tweak" to make Total Finder work on El Capitan -- AND to he honest in my view you should not be advising users to do so.
99.99% if users are likely to be exactly like me -- which is having absolutely NO Idea of what System Integrity Protection does and so also having no idea what the pros and cons are of enabling or (as you suggest) disabling it. Furthermore, your proposed tweak is no simple little thing for total novice users like me. I would be more likely to cause deep and unrecoverable damage to my system than to succeed.
I'm English so at this point I would normally ask you what ####, but your obviously nice folk so I won't; but what I will ask you to do is to tell us when your team will have a version of Total Finder that works on El Capitan without any tweaks?