It departed with the required full reserve, but flew past it.
Well ... OK. No matter the size of the reserve, if ones uses it up, one likely arrives in deep stuff. But, does the required reserve anticipate the possibility of stranded fuel due to malfunction or pilot error, or does it assume everything works perfectly? Its been a long time since I read the threads on this accident, but IIRC the required reserve might have been around 10 min. If so, IMHO, cutting it way close, especially if at night in a densely populated area. YMMV.