Unless you've got a lot of experience changing spark plugs on a 1996 Porsche 911 Turbo, I think that statement applies to both you and the GP. It's reassuring to think our problems are harder than those of other professions, but it's not always true.
If it takes longer than a week to change a spark plug on a 1996 Porsche 911 Turbo, I'd be shocked. If it takes longer than a month, I doubt anyone would ever bother. A year? Unimaginable.
For software, on the other hand, I have seen all three.
If it were between fixing an unknown issue with said car and fixing some code, then I would say it might be a wash. Fixing that particular issue with the car though? Regardless of the difficulty in fixing it, at least you've got a book that tells you what to do (I assume. I would be very surprised if that wasn't the case. From the sound of it, it looks like he knows what needs to be done). Diagnosis and design of a fix will almost always be more challenging them implementing a fix, be it with cars or code.
I'm still going with merely knowing that your job is to replace the sparkplugs gives you a leg up. You seem to have a pretty firm grasp on how complicated the task is and what is involved, which is already a head start.
In most cases no. You do have an idea of what you have to do (as in software), but nothing too exact. Worse when its an European brand that pleases itself in over-engineering everything.
Well as I said, "If it were between fixing an unknown issue with said car and fixing some code, then I would say it might be a wash."
If we're comparing an unknown with an unknown, that seems reasonable, but comparing a known (replacing spark-plugs on that particular car) with an unknown seems foolish, no matter how physically difficult that known may be.
