Grievous Wounds on Thornmail sounds like something every champ can but just to abuse ADC's further

Imagine being Ashe or something, duelling a different ADC with life steal, but she's healing and you're not, because one of your Hurricane bolts managed to hit her Thornmail-wearing support. That's simply not nice. I get the duration is just one second, but that's all it'll take to get a small, pathetic heal that costs you your life.

Couldn't there be another way? What if the passive was changed to something like "Champions will heal less from attacks they deal to you?" It'll keep people who buy the item doing their job, but it won't absolutely obliterate any chance of surviving a teamfight the ADC currently has.