[websiteguy]

(disclosure - I am the author of this article) I think this comes down to judgment.

Design appropriately. Short sighted designs are as bad as ivory tower designs. Every situation is different.

If a person does not own something, no one does - everything comes down to the individual. This does not mean that there is no overlap in knowledge.

Source control is a must. So are scripts that detect changes in your area. So are tests.