What is the use of the 'teardown'?

The 'Teardown' page is interesting but not much use. To me a teardown is a step by step disassembly, not just pictures of an already disassembled phone with 'steps' alongside that are not steps at all, just a rather superficial description of the unit, mixed in with equally interesting but pointless detail.

I want to replace a broken screen, so how much of the phone do I take apart and where do I start? This 'Teardown' tells me next to nothing of how to go about it.

Full marks for interest and zero for usefulness.