I dug into the text files for Sonic Mega Collection Plus, and there's some interesting differences. There is different cheat text for each region setting (JP, EU, US). For Sonic 1 JP and Sonic 2 EU/US, it refers to the mode as "character change": For Sonic 2 JP, Sonic 1 EU/US, and Sonic 3 & Knuckles (all regions) it refers to it as "edit mode".
Hm, from the US and thinking back I'm not 100% where I first heard the name. I know that I had my hands on lots of magazines back in the day and they often had cheats listed, but the only cheats that stuck in out in my memory are ones for Mortal Kombat II; I wrote them down on a piece of paper then tried the codes when I got home. I know around '99 or 2000 when I stumbled across the Simon Wai's site and got into the community everyone was calling it Debug Mode and I understood what that meant, but that doesn't help much when it comes to finding the original name for the mode.
I took some photos of my old 'official power tips books' and 'action replay' cheat books. circa 1992. None of them call it debug, they just kind of describe what the cheat does:
The equivalent in the Adventure games was called EDIT: These ones weren't around in the final game though, only debug prototypes.
This. "Debug mode" was standard lingo for the concept (in both Japanese and English) - many games included debug modes or debug menus that weren't removed in the commercial release. Whether or not the particular debug mode in Sonic had another name, it's still a debug mode by nature.
It seems conclusive that it was called edit mode internally, but I still think fans called it debug mode because that's what it seems to be. That was always my thought pattern. I'm not a programmer and have no idea if it really is a debug mode, would debuggers have used it? But that's what it seems to be to me.
I'm not a programmer either, but I could see it being useful to place objects to easily test their behavior, rather than having to actually find one in the levels.
It's not a traditional debugger in the sense that it doesn't monitor the program's "state" - it's not going to tell you what's in memory, or which lines of code are being executed or whatever (although it tells you the sprite count so that's something I guess). But it is a tool, and all sorts of tools are useful when you want to "debug" a video game. The level select is another tool. Yuji Naka would have had more to work with.
Literally every magazine or comic I had that mentioned it referred to it as Debug Mode so I always just called it that. I assumed it was a way for them to test the behaviours of various objects in weird combinations and stuff.
I think you hit the nail on the head. Otherwise, what are we "debugging" when using the mode? I always seen this as a test-like mode to test out objects-- because they don't stay in one spot if you move too far away from them, and you can't really 'save' your creations. So it makes more sense to call it a debug rater than an edit mode--despite what it was initially called. At least for me.
I agree with this; it's really not a leap to say something along the lines of "Edit Mode is an internal term used by Sega and/or Sonic Team for object placement debug functions created for Sonic the Hedgehog video games." What external people call it is only relevant when explaining the term. Granted, that's a really dry and boring sentence that could use some wordsmithing.
I, too, grew up using the term "debug mode" exclusively, almost certainly as a direct result of US magazines. Specifically, I owned that GamePro 29. It's always seemed very colloquial, so it's not surprising to me it's not the name that was used internally. It's wild that we have attestation of "edit mode" from that Nick Arcade module, though, what a stroke of luck.
In the Official Sega Players Guide of Sonic 1 and 2 that I scanned they called it Construction Mode. https://drive.google.com/file/d/1s6sbNGK_b8ZiABDuBsopWy6FhTVOJ9pS/view?usp=drivesdk Page 62
