Reasons why people avoid long sets with deadlifts are:
1) Many lifters can move big weights with the dl, so the stress on their body with heavy high rep deadlifts is huge.
2) There's pretty high risk of injury if there's major flaws in ones form.
3) They suck, a lot, and people are pussies.
But there is nothing wrong to train DL with high reps. I have done PR sets with deads in 7-15 rep range several times, and have noticed really good results by doing so.
So in short: Yes. Just make sure you're bracing properly and keeping your form tight. I strongly recommend you to film your deadlifts and see how they look during a long set.