Well having 112 days without out a "slip" or "relapse", at this point in time if I picked up I personaly would call it a relapse for me even if I only took a sip!
At this point in my sobriety even a sip would be a conscious decision on my part.
I "slip" on ice and accidently fall.
If I decide to drive into a brick wall that is not an accident.
I agree that someone early in sobriety while they are still in a fog may truly slip, but once the fog has lifted it (IMO) is a decision one makes to pick up, I fully acknowledge that it is our disease that convinces us it is okay to pick up, but we still decide that our disease is right, we do not fall down and a drink "slips" into our mouth.