You're saying 4 "raw" dice is worse than rolling 3 dice with a focus? Is there some math that supports this?Still worse than focus.
Yes. There's a couple ways you could probably look at it, but four unmodified reds have an expected yield of 2 hits, whereas three with a focus yield 2.25.
Yep. The math is thus:
An unmodified attack die has a 1/2 chance of hitting. So 4x1/2=2.
A focused attack die has 6/8 chance of hitting. So 3x6/8=18/8 (or 2.25)
While true and I believe Expose is generally a plain ol' bad upgrade to take, we're not being entirely fair. A focus gives better odds of producing a hit compared to Expose. However, Expose gives an opportunity for higher damage.