Impede move line deletion directly from account plan and GL

As perhaps intuited from https://discuss.tryton.org/t/iterate-with-pyson, it is a royal pain that users can delete move lines from draft moves in certain forms, notably account plan and GL… finding after the fact which move is affected is not a delightful task.
How best then to impede deletion from these forms, and only allow deletion of lines from the main account move form (or from something that creates whole moves like invoicing, statements etc…)…

I am unsure if it is doable, but adding a validation step to ensure the move is balanced before saving could be a solution ?

Seb, the move is initially balanced… it’s the deletion of a single line that fouls things up.

What I mean is when you delete a line from account plan (for example), tryton will first validate the move before saving it. And as deleting a line will make the move unbalanced, it should prevent to save an unbalanced move.

I guess I see what you’re striving at… in Oerp, the moves had draft, valid & posted to this effect.
I wonder if that’s not such a bad idea, where valid can’t be changed without going back to draft
(like invoices & statements).