We are left with following problem, upon which TcT provides the
certificate YES(?,O(n^1)).

Strict Trs:
  { anchored(Cons(x, xs), y) ->
    anchored(xs, Cons(Cons(Nil(), Nil()), y))
  , anchored(Nil(), y) -> y
  , goal(x, y) -> anchored(x, y) }
Obligation:
  innermost runtime complexity
Answer:
  YES(?,O(n^1))

The input was oriented with the instance of 'Small Polynomial Path
Order (PS,1-bounded)' as induced by the safe mapping

 safe(anchored) = {2}, safe(Cons) = {1, 2}, safe(Nil) = {},
 safe(goal) = {}

and precedence

 goal > anchored .

Following symbols are considered recursive:

 {anchored}

The recursion depth is 1.

For your convenience, here are the satisfied ordering constraints:

  anchored(Cons(; x,  xs); y) > anchored(xs; Cons(; Cons(; Nil(),  Nil()),  y))
                                                                               
           anchored(Nil(); y) > y                                              
                                                                               
                 goal(x,  y;) > anchored(x; y)                                 
                                                                               

Hurray, we answered YES(?,O(n^1))