[PvK]

Go to design screen, bring up a design, press the "to hit modifiers" toggle button. When activated, the total to-hit mods for the design are shown, including all sources, and letting you see whether they stack or not, etc.

Oh, and thinking about the original observation about to-hit chances shown in tactical - I think they might not take into acount the target's defensive abilities from their race and ship / fleet experience.

PvK