Question about thunderous strike

I am trying to understand how thunderous strike in the primal strike skill line works. It says it modifies damage by -35% and weapon damage by -75%. Does the -35% come off torrent and storm surge as well in the primal strike skill line or does it just lower the damage of the primal strike skill itself?

My next question is once they take the -75% off my weapon damage do they take another -35% off as well?

Primal Strike at 16/16 does 215% weapon damage. With Thunderous Strike, that number is reduced to 140%. Once the total weapon and bonus damage is calculated for the hit, the final number is reduced by 35%. I don’t believe either of those reductions affect Torrent or Storm Surge but I’m not certain on that.

Good info thank you!