Then I'd be alright with that distance. Does the other blind know you're there? That close, they should probably know you're over there.
If you're hunting a huge chunk of ground, courtesy might lead you to seek out somewhere not so tight. But ... Terrain, deer movement, who you're hunting with, who's in the other blind, deer density, etc all goes into the decision.
Jesus likely said it best : do to others as you would have them do to you. If you think you can both have a quality hunt, it's all good. If you know that you are messing somebody else up and they were there first then you should move.
Good luck!
-Jake