This is a good tip for working with Marabou. I have more than once tied the butt sections in dry and the butt sections flare and often require many thread wraps to secure the flare. I think this is a good tip to totally reduce flare and minimize thread wraps. This is particularly helpful in tying Woolly Buggers or any plummage tail like filoplume or chickabou. Check out Diptera.co.uk for additional good advice on the pinch technique and using a dubbing loop.