Here's another item that Nekohashi posted a few years ago. Once again the specific details are for Ryu but the concept works for various characters. The original post is here. I paraphrased and omitted some parts.
"Button Release" AKA "Negative Edge."
"Sumo Drop" AKA "Hyakkan Otoshi." Charge down, up + kick.
For this technique you take advantage of the fact that you can do special moves with a button release to throw a fireball that way. [Hold punch, down, down-towards, towards+release punch.] There's no need to do this every time but under certain circumstances it can work to your advantage.
You can use a button release motion to prevent having accidental normal attacks come out in case you couldn't throw a fireball. This means you not only guard against having that accidental normal get tagged, but you can also focus immediately on your next play.
In fact this situation comes up in places you may not have noticed. Take Ryu vs. Honda for example. You knock Honda down then throw a jab fireball that's right on top of him as he's getting up. If you try to follow up with a fierce fireball as quickly as you can, but he avoids the first one with a reversal Sumo Drop, you'll get an accidental straight punch (i.e. far standing fierce.) If that Sumo Drop hits you, he then gets a juicy okiseme chance; what was an advantageous situation for you quickly turns very gloomy. On the other hand, if you wait to see if the jab fireball is blocked you must throw the fierce one a moment later. Depending on the spacing this will give him time to vertical jump over the second fireball. A third fireball won't necessarily be safe and your barrage is much weaker.
You can avoid these pitfalls with a button release fireball. It can be done at the earliest possible moment, and if Honda does a wake-up Sumo Drop you can simply hit him with a Dragon Punch.
1. Jab fireball as Honda is standing up
2. At the earliest moment (as the jab fireball would dissipate,) do a button release fierce fireball
3. Jab fireball misses as opponent does wake-up special move, you're free to do whatever
(If the jab fireball hits or gets blocked, you'll throw the fierce fireball like normal)
4. Respond to opponent's wake-up move appropriately (DP, low RH, block)
Once you master this technique, you can shut down various attempts by your opponent to gamble with wake-up moves through the first fireball. The trick is also very handy with a super fireball. While the above example was for Ryu, you can use it with Guile and other characters, too.