Section Test.
Variable x : nat.
Definition addx y := y + x.
wlog H : (n0 := n) (y := x) (@twoy := (id _ as X in _ <= X)) / twoy = 2 * y.
myadmit.
myadmit.
Qed.
Definition twox := x + x.
Definition bis := twox.

Lemma testw3x n (ngt0 : 0 < n) : n + x <= twox.