I'm with you - I run about a 1:50 half and also hope for a sub 4 hour ascent. Like others have said, it is amazing how slow you really need to move to match the pace charts. I agree that the crowds actually help through the W's. By 3 miles in, the trail begins to open up and you still have 10 miles to push your pace if you are feeling fantastic. The past several times I have trained on the Peak, traffic from the Incline has dramatically slowed me down during the W's (mimicking race day, really), and as frustrating as that is, it has helped me realize that being 2 - 3 minutes behind in your pace at the top of the W's is easily made up when you haven't gone out too hard too early. Good luck and have fun!