I have posted in the past on this, when other users have asked, but never a responce
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I'm sure that this can be done, but on an individual case by case basis.
If you look at my piping utility, in the FREE dwgs section, this creates each block from scratch the first time an item is selected.
A block of that item is created and stored in the dwg for the next time it's needed.
ALL of the dimensions for each specific item are stored in a file for retreval as and when required.
So if the basic geometric shape is known then a new utility could be written with a dialog for dimension entry.
This would create a block to the prescribed dimensions only. If you want to change any of the dimensions, then you would create a NEW block, NOT modify the first.
More akin to Parametrics.