PCBgogo

I am interested to know how often do people use 
a) hierarchical designs/schematics with their CAD tools
b) apply the concept of design "re-use"  in their projects
- hierarchical designs means you can descent and ascent into different levels (or hierarchies) of your design instead of using 'off-pages' connectors in 'flat' schematics.
- regarding "design re-use" I mean the following: 
Assume you optimized a board layout of a switching regulator for lowest spurs, you have a version that has been verified and is working nicely based on lab measurements. The idea is that you save the entire schematic and layout  of that 'sub-circuit' as a new part in a different library. Even if the layout was done on just a two layer design, you could place it onto a 4 or n-layer board and you don't have to re-design the schematics and re-layout the circuit (provided a similar PCB class is used (via size, spacing rules etc).
I follow this approach using OrCAD and therefore have several libraries that contain 'parts' that are sub-circuits with a complete DRC clean layout view and different symbol view attached to it. So if I need to re-use a - 5V switching regulator, I just have to place a symbol from my custom library into the schematic and after netlist generation I can place the entire layout for this sub-circuit onto a new board file, rotate it, mirror it to the bottom of the PCB etc.
I am using a trivial example (small circuit) here but one can imagine how much time you can save if the concept is applied to more complex sub systems (multiple FPGAs using many bypass caps on a single board etc...)...
I am interested in responses like
- I don't care, not worth the time this would take to setup correctly
- Would be interested, but the tool does not support it (please name the tool)
- never thought about  it...but will try it 
- yup that's what we do also...
- or any other response  :-)
I am looking forward to responses.