Overloaded Methods Return Type for Type Ascription

[jeffusan]

One of the Type Ascription hint-questions is:

Is it a recursive or overloaded methods return value? Yes, you have to.

It's easy to prove this for recursive methods:

scala> class SumMaker {
     |   def sum(ints: List[Int]) = ints match {
     |     case Nil => 0
     |     case x :: tail => x + sum(tail)
     |   }
     | }
<console>:40: error: recursive method sum needs result type
           case x :: tail => x + sum(tail)

scala> class SumMaker {
     |   def sum(ints: List[Int]): Int = ints match {
     |     case Nil => 0
     |     case x :: tail => x + sum(tail)
     |   }
     | }
defined class SumMaker

scala> val a = new SumMaker
a: SumMaker = SumMaker@545d7e85

scala> a.sum(List(1,2,3,4)
     | )
res3: Int = 10

But overloaded methods do not seem to require an ascribed return type:

scala> class Overloader {
     | def overloaded(x: Int) = { x }
     | def overloaded(x: String) = { x }
     | }
defined class Overloader

scala> val x = new Overloader()
x: Overloader = Overloader@10bdc63a

scala> x.overloaded("1")
res2: String = 1

scala> x.overloaded(1)
res3: Int = 1

Did I miss something? Or is ascribing the overloaded method's return value a recommendation rather than a requirement?