To the best of my understanding it would make no sense - they are already using (I have to investigate how they achieved it technically) a single transistor to

To the best of my understanding it would make no sense - they are already using (I have to investigate how they achieved it technically) a single transistor to store the "weight", and they manage to encode an FP4 in it (through a table). No gain in having less than FP4, so.