I did the snowman legend in 2017. It was such a great race! Need to go back and do it again.
I can’t remember it being windy at all when I did it so can’t help there.
We had to take clothes on the run that would provide full body cover, but that rule was weather dependent. If the forecast is good I don’t think they have that rule, but it was fairly damp, cool and the mountain was covered in cloud when I did it. Think I took a woolly hat, gloves, arm warmers, maybe a lightweight rain jacket and water proof trowsers packed in/ on my camel back. If I did it again I’d just take the hat, gloves, arm and leg warmers - but I didn’t have leg warmers at the time so I had to take the waterproof trousers for leg cover.
The “jog” up moel siabod is a walk for almost everyone, it is very steep and the trail was more of a stream when I did it. Lots of slippy loose slate rock and a few boggy parts for good measure. I imagine maybe the leaders could run up parts but I don’t remember seeing anyone running up it - so you all go at roughly the same pace.
Where you can definitely make up lots of time is on the way down. People who knew how to run down steep uneven terrain, had the foot speed, technique and confidence could fly down. If you don’t have that you end up slipping over a lot and falling in ditches like a tit/me.