Correct me if I'm wrong, I am a newbie to the IFR world but his question has interested me.
'training wheels' is he not refering to a situation where the cloud base is above the MDA for a straight in approach, but below the MDA for a circling approach? Thus in your example if you continued down the ILS, or your GP for the LLZ to the circling MDA, you would not be visual therefore unable to circle?
The only way around this I can think of is what the others have suggested - if by day, descent to the straight in approach MDA maintain 300' obstacle clearance.
ID