I am but an egg when it comes to minion wave control. These are some my observations thus far.

Under normal circumstances when your minion wave collides with the enemy minion wave this is the formation that results.

M=Melee
C=Caster
N=Cannon

CCC
MMM
---
MMM
CCC

or

CCC
N
MMM
---
MMM
N
CCC

There will be a gap between where the melee minions line up to fight each other and the ranged minions line up, unless the minions are reacting to your presence as they will preferentially target champions if they are in range.

So, one sure fire method to get your lane... Read More