Scaup/Tufted Duck at Bosherston

Assuming that Paul and I are referring to the same duck at Bosherston, and I suspect that we are, I'm not sure that 'Scaup-faced Tufted Duck' does it justice.  I initially blogged the bird as a Tufted Duck, but had only had distant views with 8x bins and had not paid it any real attention: primarily due to the distraction of the Long-tailed Duck - a species that I hadn't seen for a few years since seeing them on their breeding grounds in the Arctic Circle :-). 
On getting home, however, I noticed that there were a few Lesser Scaup in the country and I started to feel a bit ill at ease that I hadn't checked the bird with the Long-tailed Duck.  Consequently, I scrutinised my pics of the Long-tailed Duck and came across this image of the offending Aythya duck (here in the company of two female Goldeneyes).  This pic clearly shows that the bird has a rounded head, which is almost flat in the middle (no hint of a tuft or a peaked crown), and has grey on the mantle, not great features for a Tufted Duck.  However, the bird certainly isn't a 'classic' Scaup either, as it was quite small and, with the benefit of hindsight, might have too much black on the tip of the bill.  All comments welcome......