Changing collider position results in different physics. Why?

I don't understand why this is happening. An explanation would help greatly.

I have two objects, Player and Player2. I wrote some code to move these objects. They both have capsule colliders and rigidbodies. Player2 is an exact copy of Player except I set the capsule collider center y position to 1 instead of 0.

To move the objects, I do the following code:

Code (csharp):

1.  
2. float movemax = 8;
3. //Get current touch position, check distance from start touch position.
4. //Update start position if cur touch is too far from it.
5. if(t.position.x - movecenter.x > movefromcenter){
6.     movecenter.x = t.position.x - movefromcenter;
7. }
8. if(t.position.x - movecenter.x < -movefromcenter){
9.     movecenter.x = t.position.x + movefromcenter;
10. }
11. if(t.position.y - movecenter.y > movefromcenter){
12.     movecenter.y = t.position.y - movefromcenter;
13. }
14. if(t.position.y - movecenter.y < -movefromcenter){
15.     movecenter.y = t.position.y + movefromcenter;
16. }
17.  
18. Vector2 moveamount = new Vector2((t.position.x - movecenter.x)/movefromcenter, (t.position.y - movecenter.y)/movefromcenter);
19.  
20. //Apply Velocity to both Players based on distance from touch start and touch cur
21. Player.rigidbody.velocity = new Vector3(movemax * moveamount.x,Player.rigidbody.velocity.y,movemax * moveamount.y);
22. Player2.rigidbody.velocity = new Vector3(movemax * moveamount.x,Player2.rigidbody.velocity.y,movemax * moveamount.y);
23.  
24.            
25.            

When both objects have the same collider position, they both move in unison. However, when I change the position of Player2's collider center.y to 1, it moves slower, and when I set it to -1, it moves faster.

If I'm not clear enough in my description, I can supply screenshots.

My question here is: why does the object move differently if I adjust the collider's position?

 

bump?