If you breed a Platinum x Normal, statistically half the babies will be Lesser and the other half "normals". Everything that is normal looking from a Platinum parent is 100% het Platinum. Breed a het Platinum to any Lesser or Lesser combo and you have the potential of producing Platinums. The het Platty will ONLY react to the Lesser gene (just like Special and Mojave, and YB with Specter, Spark etc). So if you breed a het Platinum to something like a Queenbee (a breeding I'm actually doing this year) you can make Bumblebee Platinums, Spider Platinums, Pastel Platinums, Platinums, Lesser, Pastel Lessers, Queenbees, Spiders 50% het Platinum, Pastel 50% het Platinum and Bumblebees 50% het Platinum.