controller.simplemove having issues with vector3.forward

EDIT: See my comment response below this post

I am trying to simply move my enemy forward (using the character controller) by calling SimpleMove.

First off, I got this to work no problem with my player class. I copied the bits and adjusted them and applied them to my enemy class and its not working. The enemy sort of jerks in the forward direction for a few frames, then immediately goes the wrong direction for about 1.5 seconds, then jerks into the forward direction, etc...etc...

I've included this wonderful illustration to show what I mean. He move forward, then slides the wrong way for a bit, then forward. I have the character controller and character motor set up identical to my player class and its just not working. Any ideas?

using UnityEngine; using System.Collections;

 public class EnemyController : MonoBehaviour {
 public int health;
 public AudioClip hit;
 public AudioClip die;
 float distanceCheck;
 Vector3 desiredDirection;
 public Transform PlayerPosition;
 public float runSpeed;
 public float rotationSpeed;
 CharacterController controller;
 // Use this for initialization
 void Start () {

 animation["gethit"].layer = 2;
 animation["gethit"].speed = 1f;
 animation["waitingforbattle"].layer = 1;
 animation["die"].wrapMode = WrapMode.ClampForever;
 animation["die"].weight = 1;
 animation["die"].layer = 3;
 }
 
 // Update is called once per frame
 void Update () {
     controller = GetComponent<CharacterController>();
     distanceCheck = Vector3.Distance(PlayerPosition.position, transform.position);
     desiredDirection = (PlayerPosition.position - transform.position);        

     controller.SimpleMove(transform.forward * runSpeed);

     if (health <=0)
     {
         animation.Play("die");
         animation.wrapMode = WrapMode.ClampForever;
     }
     else        
         animation.CrossFade("waitingforbattle");
 
 }
 
 public void getHit(int damage)
 {
     health -= damage;
     
     if (health > 0)
     audio.PlayOneShot(hit);
     else
     audio.PlayOneShot(die);
     
     animation.Play("gethit");
 }

}