Resume Length

The skill of writing a CV to reflect all your relevant talents and qualifications is also something to compare.

If I read the CV of engineer 1 who tells me he can do X Y and Z and was recognised by authority A I'm going to be more interested in inviting him for an interview to see if he really does know X, Y and Z than engineer 2 who tells me the minunatae of everything he knows because not only is my time limited, writing War and Peace no more proves you can do X than writing 'I can do 'X' because you could simply have someone who really does do 'X' to write your CV for you.

Keep it short, relevant and personal and be ready to back up any claim you make in the interview.

Why would you need to read through them all? You read the first page and save the ones which catch your interest, just like you do with everyone else. Except now that your interest is caught, you have the added convenience of reading more in depth about the applicant's skill set and another chance to be impressed. Everyone else with their single page resumes do not have that advantage.

Any more than 2 pages and it looks like you're long winded and full of crap. 

And seriously, how many words does it take to say all the types of welds an experienced welder can do?

Why is it that teachers, colleges, recruiters, and virtually everyone I've met recommends to keep a resume down to one page, or two pages at most?

If you are hiring a doctor, would you rather hire a doctor with a 1 page resume, or would you rather hire a doctor with a 10 page resume?

There is something to be said for being concise with your top accomplishments. Packing your resume with mildly impressive to mediocre filler, wastes everyone's time and paper. I cannot imagine a single instance in which including only absolutely incredible credentials would take up more than a page unless you suck at formatting.

A few Nobel prizes, a few PhD's from certain institutes, invented holographic simulation technology, cured cancer while rescuing a baby from a burning house filled with bears...  7-10 lines. 

Circling back to programmer examples, he can briefly describe his proficiencies within certain languages. Knowing exactly what he knows and exactly what he has done is pointless, because you only need to know his general area of expertise and if he can learn new skills relevant to the job. No programmer is ever hired to write a program they've already written. Programming jobs are all about having a base knowledge, and doing R&D post-hire.