Crown of Eyes - Iron Will/Iron Grip?

If I were to use Crown of Eyes with Kinetic blast(for example), I equip repentence which gives me iron will, so I get an extra 1% spell damage per 5 str which equates to an extra 1% attack damage...

If I then link iron grip to my kinetic blast, will I get 2% dmg/5str (1% from spell/attack and 1% from projectile) or will it only provide me with 1% total since it is the same str providing the bonus for both?

yes, you asume correctly that a single modifier cannot affect one damage type twice