"If one ceases offering one’s patents under the DPL, previous licensees keep their DPLs royalty-free, but the leaving user may have her licenses converted from royalty-free to fair, reasonable, and non-discriminatory terms (FRAND) at the discretion of the remaining licensors." -http://www.defensivepatentlicense.org/content/frequently-ask...

I'm worried about how this would affect someone's employability. Could this "poison" your work in the eye of a corporation's legal department?

Anything could "poison" your work in the eye of a corporation's legal department.