Border Terrier's coats need to be stripped when they get long (I call it "plucking" like a chicken LOL). You can clip them if you like but it does change the texture and weatherproof qualities. However, Zack's coat never seem to grow. It takes forever to get any scruffiness to him. I love when he gets scruffy and shaggy hair round his face but it seems to take a liftime. I guess I am lucky tho as he is low maintenance and if I had a border that's hair grew fast I probably would be cursing that too.
Zack hasn't been plucked since October 2010 and I was hoping his hair would grow in for the winter for warmth but it has only thickened and not really got any shagginess to it. I am just going to leave his coat for the next little while and see what happens. Probably he will start to look shaggy in May when it is time to pluck him for the summer to keep him cool. LOL. I see other border terriers whose coats look like shagginess on four legs but I don't think Zack will ever get there. I love him just the way he is tho hair or no hair!!! LOL