> A better question might be "Why are you interested in building X for Y industry?"

If the JD is building X for Y industry, I'd think a cover letter might address this. Sometimes, of course, we're in the position of doing a bit of spray-and-pray when it comes to application...but generally I try to make sure the cover letter justifies sending the resume at all: here's my interest, your needs, and some more information if you want to read further.

> What's missing is clarity and direction for the less quantifiable bits. Done right, it could be like a low-pressure, no-expectations first interview in lieu of a crap email that's tedious to write, tedious to read, and likely only helps a hirer understand whether the applicant can write a good cover letter.

I think you're basically right here: the interview process is challenging because it's a bit like a first date and you really want to know what the marriage is going to be like. That's why, I think, some companies have shifted away from being very clear about what they're asking for and more towards trying to find personality, adaptability, and retention fits: it maximizes their ROI by ensuring they get people they like, who can change as needed, and who will stick around. The challenge for applicants, of course, is that they no longer really know "What am I going to do?" and "Am I qualified for this?" or "How much do I need to learn?" There's a lot of comfort in competence!

I wouldn't underestimate the value of communication—including the ability to write a cover letter. I resented, at first, that I found myself in more forward-facing positions in my career, because I wanted to spend more time in technical work. But it's been a suitable way to get paid while enjoying time programming, too.

> What is the response rate to those postal mails you send? And who do you address them to (do you find the name of the recruiter or just address it to the general company)

I don't do this often, so I'd be wary of reading in too much. In each case, I got an interview and one job, though that took awhile. (The hiring manager did not comment on the letter, but rather on the table at the top—probably because I couldn't find his name.)

I try to find the appropriate person to contact through LinkedIn, ideally a manager in the department of interest; I wrote to a (small) company president once, too. I try to avoid recruiters if I can help it, though my bias against them is perhaps a little uncharitable. The goals are two: to sidestep the usual application process through a little elbow grease and to differentiate myself in the candidate pool. I'm probably a pretty average programmer, and this has been a useful tool for me.

In the past, cover letters were usually a weak point because I would use boilerplate language that comes across as a bit canned. I've had the luxury lately of not having to do this: the letters were all written for companies I thought I really wanted to work for, so the interest was genuine and (hopefully) came across that way.