I once had an instrument student flying a C172 ...Often it was IMC and always in the dark (winter time in Pac NW)... Did we ever get ice? You bet.
Your Cessna 172 was the one and only Skyhawk certified for flight into known ice, then? No apologies there...you knew you were flying illegally, and demonstrated to your student that it's okay. What a wonderful example for an instructor to give a student, when the intructor is there to develop wisdom and judgement in the student. Excelent effort.
But we had outs that would allow us to escape to safety if need be.
Well then, this makes it all right. Illegal and unsafe (ice in an aircraft not type certificated or ammended for flight into known ice is an unsafe and illegal condition. As you are required at all times to be both legal and safe, and the very definition of airworthy means the aircraft is legal and safe in all respects, means that you made the flight in an unairworthy airplane, under illegal conditions, taking on ice at night in an aircraft not certified for it, while providing instruction to a student. Not only are you unrepentant about it, but you're defending your action as though it were a good thing.
It's not.
There was nothing ever cavalier about it, and we both feel that the experience and confidence he gained helped him in his flying.
Apparently so. You feel that flying a student in icing conditions in the dark in a single engine airplane not certificated for flight into known ice was good experience for your student, and your student now has the confidence to do things he shouldn't, thanks to your fine example. And you find this acceptable. Perhaps your're even proud of yourself. Fine job.
I guess what I'm getting at is that you should fly at the level you feel comfortable with, but do not pass up the opportunity to stretch your abilities (with proper preparation). After all, the plane flies just as well at night and in clouds as it does during the day in the clear.
Does it fly as well in the ice as when not in the ice? Is it okay to
fly in ice at night because you feel comfortable? Are you stretching your abilities by performing illegal and unsafe activities in unairworthy aircraft? (But it's okay because ou feel comfortable...).
It's okay, Mr. Inspector. Yes, it's a violation of the regulation, but don't worry. I'm comfortable with it.
You have the situation clearly in hand and under control. Again, my most sincere congratulations at your elevated state of justification...the narcotic of the soul. How is your addiction today?