Instrument instructing in a twin without MEI

The regs are very confusing about this, I looked everywhere and apparently the wording was changed 10 years ago and now it isn't as clear to the answer. From 61.196 "(2) If the flight instructor is conducting the instrument training in a multiengine airplane, the flight instructor must hold an instrument rating appropriate to the aircraft used for the instrument training on his or her flight instructor certificate and meet the requirements of paragraph (b) of this section." Ok so they literally have the exact scenario there, and it seems like all they would need is a MEL rating an IR with mutli add on, but then back to paragraph (b), which says: (b) Aircraft ratings. Except as provided in paragraph (c) of this section, a flight instructor may not conduct flight training in any aircraft unless the flight instructor: (1) Holds a **flight instructor certificate with the applicable category and class rating**; (2) Holds a pilot certificate with the applicable category and class rating; So why even have that part about instrument instruction in a multi since section C already talks about them needing an instrument rating for multi engine. And then (b) clearly says category = airplane, class = multi engine. This reg seems needlessly complex if they dont need an MEI and if they do then why don't they just outright say that in section 2 about instrument training. Any thoughts?