I have read that plants are actually their most efficient at processing/growing/doing the things plants do at night. The problem for plants of course is that at night there is only a limited supply of resources (basically what their roots hold/store) due to no photosyn-howeveryouspellit-thesis. So I'd probably suggest that lots of oxygen and carry on watering them. Also the story with the full moon is that the full moon is reflected sunlight and its lumin count and probably it's entire spectrum makeup is very different to standard daylight. You never get a suntan of anykind under a full moon (even if you could get one for enough time which isn't really feasible). So my inexperienced view on watering is that plants need a degree of water available all the time for their roots, as much oxygen as possible and I suspect that they are rather responsive to changes in their enviroment - if maturity of the plant and it's life-cycle is determined by photoperiod rather than by age then it may be rather important to ensure a well maintained dark period. Plus wouldn't it be better to err on the side of caution and water at a different time - if that's all it takes for you to produce nicer buds then why not?