I have a vague recollection from way back in college of one my professors saying something to the effect that after only 3 weeks (on average) of not looking at the code for a program, studies showed the original author of the program had no benefit working with/maintaining that code vs a developer who had never seen the code.
Going back I want to find a source for that statement, but I can't find it anywhere. Am I hallucinating? Or can someone point me in the right direction?
Speaking strictly from my own personal experience, I would call nonsense on that statement. I've gone back, many times, to code I've written months before and still had a much better understanding of what / why / where / how than I would have had with any random piece of third-party code.
As for the source:
“Any code of your own that you haven’t looked at for six or more months might as well have been written by someone else.”
Eagleson’s Law - Who exactly was/is the Eagleson in question is not obvious
I've found that this statement is true but the time in question is variable. I've heard 4 weeks up to 6 months.
I can tell you from personal experience that I was just shuffled off onto an "emergnecy" project from the project I'd been working on for over a year. I spent about a month on the "emergency" project and when I got back to my old project, things were a little fuzzy. I didn't completely lose touch with the old project but I had to take a minute and recollect where I had left off, what I had finished, what I had left to do etc..
Unfortunately I can't point you to a definitive answer. I think this is more of a colloquial saying than an actual proven fact. I do recall my professors in college telling me the same thing although they never quoted an actual source/author for it.
I think the 3 weeks is wrong. I never read or remember that after 3 weeks someone new is good has the original author.
For sure I won't be comfortable in 3 weeks has I would be few hours/days after just written the code but 3 weeks is pretty low. Maybe 1 year is a better time set to see less difference and still... once you read again your own code and your own comment usually you remember what and why the code is written in a particular way. A new person won't understand the deep sense of all your code as fast as the original author...