The gallows intrusion, the baseline jumps and multipass

[davidjackson]

Of course, if you are just shuffling the contents line-by-line, you can estimate in advance how much space does your original sample occupy, and you can plan the plotting in advance, without risking to run out of space. But if you are doubling the lines by plotting the stuff in half-lines, as in my last example, such advance estimate is difficult.

Scribes were taught to rule pages to ensure exact line height in manuscripts.
The lack of such lines in the VM has been the cause of much speculation.
Now ruling would not be a cause for comment, it being something common.
So, the lack of ruling either indicates that there was a reason for not ruling - or that the scribe was not presenting for a formal audience.

On a separate note, I would suggest that <1,3>,<2.2>,<2,5> in your image above argues against BTT. The lines have clearly been written from top downwards, and the scribe finds the occasional uptick hitting the lines from above. the lines below appear above the lines above.