Well then, if that's what you're getting at, and also saying that you can
Oh FFS, drive your awesome fully sick C172 down the ILS at 70kts groundspeed if you must, but I think you'll find it'll go better at 120kts, less drift etc...
Then you're just plain wrong.
Max speed for IFR final in a C172 is 100 knots.
It is and always will be a performance CAT A aircraft.
Edit
J3, you are aware that CAR 217 is only applicable to aircraft with a MTOW >5,700 kg, aren't you? Or do you have a really big C172?