is there any reason to use "spinning slash" combo on drk?

[Nedkel]

It does less damage than the syphon strike+souleater, it doesnt heal us, doesnt give us any MP, it doesnt really benefit a lot from dark arts.
The enimity thing doesnt look so good, it just seems useless since we could use Unleash once and everything around is already taunted for the cost of some MP.

Does the enimity from that combo counts for just one minion or for everything around me? I found myself not using it at all, and still being able to keep enimity even with the teams way stronger than myself.

I ask because i want to get rid of it and use these 2 buttons for something else, making it easier for me (im on ps4).