Thanks for ALL the comments...
I did hand wash, without soap, taking care to remove insoles and even using a toothbrush (the grit has also helped remove stubborn fruit peel from back molars). Still bit whiffy, mind, but looked great for at least the first 50 metres of the Lochaber marathon monsoon
I'm grateful for the wise words and I won't put any 'gutties' through the washing machine. Maintaining the structural integrity of a 100 quid pair of shoes is important stuff. More accurately, value for money is very close to a Scotsman's heart (also known as his wallet)
Not ever (financially or ethically) going to be in a position to buy, wear, clean, dry and rotate several pairs of shoes to be honest. Sounds impressive, though - obviously I'm not taking this running malarkey seriously enough. I'll take myself off to a dark room and have a word.
NtS