So I guess I need to approach this with at least some attempt at logic. Reboots are not easy things to pull off, let alone pull of well. I mean, it didn't work out well for New Coke and I suspect that comicbook publishers are somewhat below megalithic beverage corporations in terms of stick-to-itiveness.
Let's start by looking at the general anatomy of a reboot. These things happen in two parts. First, you have the decision on the part of the creators/publishers to reset or retcon parts or all of their creation. Then you have whatever happens in story to achieve said reset. So Judd Winick slips Geoff Johns a sawbuck and Superboy-Prime punches Jason Todd back to life. Or whatever. You know you're in the midst of some form of reboot when you have characters saying "Actually, I..." or "Now I can reveal that..." or Johns takes up writing duties.
I kid because I love, Geoff. More Booster Gold, please.
Anyways, this format works because it pre-answers the longtime reader's continuity questions about what the hell just happened. Didn't Joker kill Jason Todd? Well, actually, you see what happened is Clayface blah blah blah.
For the little stuff, it makes things easier for comicbook writers who go to conventions. This way, they get to brush all the "In issue #231, Hyperman says that he doesn't like fish, but in #549 he takes Bustier out for a seafood dinner! What's up with that, Mister Writer, huh? My suspension of disbelief is just destroyed by this flying man with laser fists suddenly liking fish after he said he didn't!" comments aside. "Well, remember that in the Forever Crisis storyline, the very foundations of reality were shaken when Gaspode the Delicious Boy sacrificed himself by leaping into the maw of Memnoch with a quantum grenade. This is where Hyperman's deep abiding love of fried clams came from. Doi."
For the big stuff, like Jason Todd coming back to life, this lets writers surprise longtime readers with a shock reveal. ZOMG it's Jason Todd! WTF, brah?
I guess this helps keep long running series fresh, but it is also the exact sort of thing a reboot designed to make things more approachable for new readers should avoid. The hell do I care that Jason Todd is alive. I just picked up a comic about Batman. He was totally fighting this dude with a red hood who was sort of like Batman, except he killed badguys. But then Red Hood took off his mask and everything got all weepy. The hell? Just punch the guy, Batman!
It does not matter to the new reader that Jason Todd's career as Robin ended pretty much the same way Carly Smithson's musical career did (via phone poll, not crowbar). See what I did there? American Idol circa 2008 reference. Topical. And if you think that a reference to a three year old failed TV gameshow contestant is dated, imagine how dated a reference to a sidekick who died 17 years before is.
So the new reader then has to be taken out of the story and have all this past history explained to them. Ungh. Weren't superhero comics about adventures and daring-do? Why am I getting this history lesson? There's a huge difference between exposition that sets up the plot and exposition that retroactively justifies it.
So you know what? For my reboot, no in story explanation as to why it happened. Skip Flashpoint. Who cares? The whole point of the reboot is to make things move forward, so why waste so much time looking back at the past? Who cares as to why everything is different-but-the-same now? The characters certainly don't. These are people who have to deal with alien invasions, mind controlling gorillas, and possibly turning into a robot at a moment's notice. They've probably learned to accept all the changes that come with living in a comicbook universe long ago.
The only people who care are longtime readers. Readers whose numbers are dwindling. Readers who are not the target for the reboot in the first place. And really, pissing them off is probably a good idea. "When fans are angry, we're selling comics," says Tom Brevoort.
So fuck'em. Number 1s all around. Let's reboot this shit.