Witness this GHCi session:

rae:09:18:37 ~/ghc/ghc> ghci -ignore-dot-ghci
GHCi, version 8.0.1: http://www.haskell.org/ghc/  :? for help
Prelude> :set -XTypeInType -XRankNTypes
Prelude> import Data.Kind
Prelude Data.Kind> data Foo :: (* -> *) -> (forall k. k -> *)
Prelude Data.Kind> :info Foo
type role Foo phantom nominal phantom
data Foo (a :: * -> *) k (c :: k)
  	-- Defined at <interactive>:3:1

The output from :info is terrible, treating k as a visible parameter when it isn't.

This is spun off from #13399 (closed) but is not tightly coupled to that ticket.