I think you are confusing LOD Length On Deck with LOA Length Over All.
As I see it:
LOA is just that and it doesnt matter what you do to the bow.
LOD would be effected by how the bow is raked.
Here the most used dimensions regarding lenght are Hull Length, LOA and LWL.
The Hull length is not necessarily the LOD since many times the transom is bigger than the deck. What I mean is that when you use an inverted bow the Hull lenght that normally is measured from the beginning of the bow on the deck (where the stay is fixed) will not be measured from there anymore but from the forward tip of the bow, even if for design purposes, regarding the deck, rig and boat interior what counts is LOD or the interior space in the case of a very inclined bow.
For a given purpose you will not be designing a smaller boat on the deck and interior space when using an inverted bow instead of a vertical or slightly inclined one, so in fact you will get more buoyancy using an inverted one.
This was what I meant to say. Of course if you maintain hull length you will have not only less buoyancy on the bow but also a smaller boat not only on LOD but also in interior volume and space and what makes sense when talking about a similar sized boat is interior space not LOA.
Better with a design. Here we have the same boat that has originally an inverted bow:
If a more traditional bow was used the bow buoyancy would be smaller for the same LOA: