The answer is simple. If you cannot see the ground in front of you (night) over which your flight path will take you, then never descend below the circling MDA until on final approach. At night it is impossible to judge obstacle or terrain clearance unless you are over water. The critical obstacle that determines the MDA is rarely displayed on the instrument approach chart and spot heights are not always shown. If you decide to descend below the published circling MDA on downwind or base in an attempt to fly a comfortable profile then obstacle clearance becomes entirely your own responsibility. The lawyers will have you if you live to tell the tale. And rightly so.
If it means the MDA will make it impossible to descend until on final and you will then be too high for a stabilised approach, then simply divert or try an alternative approach. Rationalisation is potentially dangerous.