Scaling Question at negative interaction speed for surgical kit/bandages

So my understanding is both bandages and surgical kit have 50% scaling on Regular Interaction speed (this page says only surgical kit, but the bandage page says it also has 50% scaling).

Does this mean, if you have say -4% regular interaction speed (about Barb/Cleric base), the (1+rate*scaling) would be 98% for bandages/surgical kit, and then 96% for every other interaction? So at negative interaction speed, there's less of a penalty for healing items/

It's just a weird part of the formula that I noticed.