Type projection and implicit resolution not playing nice

type_proj_imp

trait Plat[P <: Plat[P]] {
  type Keyed[_, _]
}

class MPlat extends Plat[MPlat] {
  type Keyed[K, V] = (K, TraversableOnce[V])
}


trait Prod[P <: Plat[P], T, This <: Prod[P, T, This]] {
  def name(str: String)(implicit wrap: Wrapper[P, T, This]): This = wrap(this)
}

trait KProd[P <: Plat[P], K, V] extends Prod[P, P#Keyed[K, V], KProd[P, K, V]]


object Wrapper {
  implicit def keyedWrapper[P <: Plat[P], K, V]: Wrapper[P, P#Keyed[K, V], KProd[P, K, V]]  =
    new Wrapper[P, P#Keyed[K, V], KProd[P, K, V]] {
      override def apply(p: Prod[P, P#Keyed[K, V], KProd[P, K, V]]): KProd[P, K, V] = throw new Exception("we made it!")
    }
}

sealed trait Wrapper[P <: Plat[P], T, This <: Prod[P, T, This]] {
  def apply(p: Prod[P, T, This]): This
}

// The following fails, I want it to be able to get the implicit which works
(new Prod[MPlat, (Int, TraversableOnce[Int]), KProd[MPlat, Int, Int]] { }).name("hey")

// this is proof that the implicit is in scope and works on the given type, it's just not being found
keyedWrapper[MPlat, Int, Int](new Prod[MPlat, (Int, TraversableOnce[Int]), KProd[MPlat, Int, Int]] { })