Guild Wars 2

your math is right! actually: 0,90 (bird one doesn´t) * 0,93 (bird two doesn´t) = 0,837 (no bird hits)…
1 – 0,837 = 0,163 = 16,3% (bird one or bird two or both hit) (both ofc not possibly because of internal cooldown)

+1 for “upgrading” Soldier Runes!!

Now remove a condition of all your allys affected by your shout