Sorry to hear about the shortened race...it really is a bummer when you have travelled a long way. It is not the first time that has happened. The race was shortened a few years ago for the same reason. A major concern was for the safety of the summit marshal who was literally unable to stand on the top which is very exposed. There is no natural shelter anywhere near the summit. I presume the same factors applied this time.
Iain, I pretty much share your views about racing in bad weather and taking responsibilty for your own safety. I prefer racing in such circumstances. However, all of us in S Wales bear the scars of being involved in the death of a female runner in very similar conditions at the same time of year. The organiser, Derek, is a great bloke and a stalwart of the S Wales running scene for over 20 years. The decision to shorten the race would, I am sure, have been made for the best reasons and not taken lightly.
There isn't really a decent low level alternative. This is complicated by the fact that it is lambing season. If anyone is interested in reading the organisers views first hand, his race report is here: http://www.wfra.org.uk/
Many moons ago, Toffer and I travelled up to N Wales to do the Welsh 1000m. The high level race was abandoned due to bad weather and a low level alternative substituted.. That really didn't suit us so we eschewed the race and did the high level route anyway. WOW! We got blasted to bits on the Carneddau, drenched out of our skins on the Glyderau and when we reached Pen Y Pass, we were informed that no-one was allowed onto the Snowdon tracks because the winds were exceeding 100 mph at the summit. We did'nt get to race or even complete the thing but we had a memorable day out.
If the shorter race didn't satisfy you, you could have always gone for run afterwards.