Leading Question
This model (see phone) can be used to explain the regioselectivity of the alkene hydrosilylation step (see figure above). Platinum dioxide, or Adam's catalyst, is used for hydrogenation and hydrogenolysis. Using the Adam's catalyst with H-SiMe2Ph produces a complex similar to the image shown above. The platinum inserts itself between the hydrogen and SiMe2Ph. When this complex forms, the SiMe2Ph will likely to attach in a linear fashion when approaching the alkene bond due to steric hindrance. This is why the addition of the silicon compound to the primary less hindered side of the alkene is seen in these types of reactions rather than the addition of the silicon compound to the more substituted side of the alkene.