I am a tipper. You are only aiming to move the developer that has become exhausted and it should be moved as consistently as is manageable. Fluid mechanics is way out of my league but I can concur that tipping works well for me.
Originally Posted by Ka
Although you did not mention it, I don't tip for 35mm as it often leads to uneven development at the sprocket holes, where the fresh developer streams through... in those cases I use rotation.
Have you considered 4x5 and dish development with the joys of n+? There are two bath techniques or my own favourite of soft working compensating developers. Not to mention plus or minus water bath in between developing stages? Only joking.