From the user’s perspective merging behaviour is basically identical in all of these systems. Ah, ok. Neat. I’m not sure what you mean about materialising are

From the user’s perspective merging behaviour is basically identical in all of these systems. Ah, ok. Neat. I’m not sure what you mean about materialising areas differently? I meant finding the ranges of the document that have been changed relative to snapshot x and showing them based on the user id who changed them. If that can be done in real-time as the changes come in that would be really impressive.