One issue with reactions to Carpenter is that they tend to assume that we can get clarity around how technological change affects what a search is by making up various artificial models for how telephony systems and search processes work. The principal example of this sort of model being Orin Kerr's description in his Lawfare piece.
|Example random model Orin made up. :)|
If you want to find out when a particular search started or ended, you almost always have to develop a lot of expertise in Quantum Mechanics, starting with Heisenburg, but quickly moving into the theory of computation, etc. This is a good hobby in and of itself, but probably more than a legal professor wants to do.
So I recommend a shortcut. A search is anything that can tell a reasonable person whether or not someone is gay. It's simple and future-proof and applies to most domains.