[bacon_waffle]

I've rebuilt several motors, transmissions, various other mechanical contrivances. Sometimes with decent documentation, sometimes not so much. Also done a bit of amateur machining, and worked as an engineer on physical products.

Under no circumstances would I claim that rebuilding a motor was essentially figuring out how to build one from scratch. In software, maybe that's like claiming that figuring out how to configure a new Linux box is essentially the same thing as figuring out how to write an OS.

[kragen]

yes, i agree. what i was trying to express is that rebuilding a motor is generally strictly easier than building one from scratch, because it's building a motor from something more than scratch. i don't think i expressed it very well

(i mean, if all the parts of your engine are trashed, you are going to have to machine replacements for them, and that might actually take you longer. but it's clearly achievable given that people have built internal combustion engines without a working example to take measurements from)

[bacon_waffle]

Ah, that helps, thanks.

It's a bit academic, but set theory doesn't really apply to such fuzzy human things as knowledge and experience. Repairing and designing are different pursuits which might have a lot of similarities, but I wouldn't presume that a design engineer could competently do the work of a technician.

Just consider that any particular field of engineering as might be described by a lay person, can be far too broad and deep for an individual to be competent in all facets of it. I'm reminded of my neighbour asking for some help configuring email for her new iPhone, because she knows I do computer work. Mainly firmware.