Let G be a GPA which produces a chain longer than twice the length n of the germ. Is G '(s) = G (s1, ..., s_ {n / 2}) (where n / 2 denotes the floor of the division of n by 2 and s = s1, s2, ... , sn) is necessarily a GPA.

For the same G as before, is G '(s) = G (0 ^ {| s |} || s) necessarily a GPA?