I'm with Pat.. this used to scare me, but it works just fine. I start thickening the limb maybe just before the bottom of the "V" of the splice. Then get a good fit and wrap it.
I personally like Mollies with a 2/3 working limb, 1/3 lever. Are you counting the distal fades as part of the working limb? With 18" limbs, 2-3" transition, and an 8"" handle/fades section, 10" levers past the splice would get you in the 66-68" range. Adjust according to your needs.