Traditional solver will make factory planned item count minus ingredient consumption.
Matrix solver will produce more ingredients to satisfy consumption.

Example: 700 iron plates with the enriched iron chain. Balanced produce 700 minus 4.698 for sulfuric acid and matrix 704.698 iron plates that include plates for sulfuric acid.

Not sure if it is bug or intended behavior.

Mods: Krastorio 2 + Space Exploration

Appreciate the report, I'll pass it along.

Scott, who wrote the solver, says this:

I haven't tried reproducing his exact setup, but it sounds like intended behavior. It sounds analogous to mining 100 coal/min using burner miners. Should that 100 be the net output or the total amount being mined? The matrix solver would produce slightly over 100/min in order to power its own setup, and make 100/min the net output. The sequential solver would produce 100/min, but the net output would be less than 100 if some of that coal was redirected to power itself. This isn't a bug, that's how you want the calculations to work.