How quick is your approach to the line? If its rather quick, slowing the approach will help and also help with the transition to a slide. So many planters have a quick approach and it helps generate speed and the plant helps generate lift. Neither really needed with today's bowling balls imo. If the ew shoes you bught have interchangeable soles, you can work with the soles that give the most stopping power, get use to them, then change the soles to slowly let you slide more and more until you come up with a combination that allows you to slide, yet get the power you want and lessen the stress on the knee from stopping or planting so quickly.
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Nicanor (Ten On The Deck)