@Jim, I am rooting cuttings from last winter, taken between the months of December through April. If properly looked after, most cuttings can remain viable inside a refrigerator between 34-40ºF for at least 3-4 months. I had a problem where one baggie slid behind my veggie crisper this year and I lost track of it for 3 months, and it molded over completely, so it's possible to lose cuttings that are placed in the fridge if you don't watch them. You need to check them every 2-3 weeks to make sure the newspaper or towels you wrapped them in are still slightly damp, and make sure mold hasn't set in. I like to double-bag my cuttings because I've found bags with holes in them. Clean your hands really well any time you're handling them so you don't introduce any 'food' (contaminants) from handling the cuttings, and don't over-moisten your towel or sphagnum or whatever you use.
@Dan, I didn't take anything you've said personally or negative, I know where you're coming after our many conversations on this and other topics in the past here, at GW and by email. I admire and respect what you are doing. I will remind you of one thing I have said a couple of times to you: I put rooting process in terms that the average human can understand, and will forever do that out here in the public, because I'm talking to the average individual who is just getting started to try and help understand basic fundamentals. I don't like to put on my engineer hat and explain the compexities - many of which I know, understand and practice but do not share - and the exact science behind rooting, because the average person I've spoken with who is just getting started doesn't need or want to absorb that kind of information to achieve a little success when they're just getting started.
At the end of the day, I'm not one to teach a toddler how to make their own aspirin (acetylsalicilic acid) by mixing salycilic acid with acetic anhydride, phosphoric or sulfuric acid, ethanol and distilled water (or whatever, I haven't done that lab since I was in college two decades ago). It makes more sense to explain how to make it to the store, find the bottle, open it, eat a tablet, then drink some water to flush it down. I respect the level of science you choose to take things down to and hope you understand that I do inherently respect you for it; it is really interesting for a couple of people and admirable to see, but I feel that level of detail is often intimidating and frustrating for newbies or folks who just want something that's "good enough" to produce a tree or two per half dozen sticks they receive. Besides that, I think adding the element of "luck" into the equation - knowing that luck does play a role in rooting, no matter how (in)significant - it keeps it fun and challenging without requiring a degree in rocket science, y'know?
You know I'll never knock you for what you're saying. And you should know I don't disagree with what you're saying, I just choose a different path to teach and share ;) And I think that's OK - at least, I'm OK with it if you're OK with it. I realize some things are "lost in translation" when you simplify them, oversimplification doesn't lend to the precision accuracy I think you prefer to relay. I'd rather practice "K.I.S.S." (Keep It Simple, Stupid) and provide a way to some early success ... which will inspire more learning and efforts ...rather than "scare 'em with big words" and lose them before they get started ;)