Well the timing for effects goes continuous or blanket effect, then triggered traits then reactions. So lets say something like the Commander action Unexpected Support targets a guy and he tries to straighten. The effect Unexpected Support put in play would hit first and negate it. So when Hida's XP trait would be triggered, he's not straightening anymore and should leave the effect unused until the next time he tries something.
I think the Guidance is quite good in a deck full of bow actions like the berserker deck. Helps Yamadera, Fortitude, Nikaru and anything else you throw in like Entrenched Position stick. Sets up Mimori to knock em out of the park. Could be good in Scouts and Seige, but I expect others will win out. Still, would make Disrupting Communications even that much better or Strategic Sacrifice keeps them down for sure to gain more honor. Jurojin's is still just so strong for scouts (or any deck really) and Ebisu's helps the Seige theme of stupid high province strength honor switch.