By 2 blend cases, I meant the translucency and additive blend tables, sorry I wasn't very clear - SRB2 currently supports several blend modes, in addition to the regular translucency blending which used to have; I believe they are internally generated on game launch, but they're there, each with their own set of tables like the translucency has.
I am aware that, as far as regular translucency blending goes, due to the way the intervals are set up, the 10% and 90% tables are transposed counterparts, and the same goes for 20-80, 30-70, 40-60, even 50 with itself. And I believe this also happens with the additive blending mode. So what I understand you're suggesting is to recycle the tables with redundant transposed equivalents.
What I meant earlier is, that I believe the rest of blend modes don't meet this transposition rule due to the nature of their operations, and thus you could no longer apply this transposition trick on them.