Smack in the middle of the 504kg band when I weighed him this evening, so the weight has restabilised.
Ross Barker (http://www.progressivehorse.co.uk/) came out to have a look at his feet on Sunday morning. His verdict was that Merlin is about 75% of the way to having perfect barefoot hooves - his soles are thick, his hoof wall is thick and there are no rings in his feet, indicating his digestive system is pretty good as well. What we need to work on are his frogs and his digital cushions and that will come with regular work on harder surfaces, though in an older horse like Merlin the digital cushion can be very slow to build up. Ross also suggested getting some hibiscrub to disinfect the central sulcus every week or so because they can be prone to infection in the wetter half of the year.
The weather stymied us for getting out for our plods last week and next week we may get the snowstorm currently bothering north America, so I'd better get him out and about a bit this week if I can.