Thanks Magus, you're right. Does anyone knows of any other throws that has hitlag ?
I added 2 sections about teching, which are also very important :
How Smash DI helps edge teching :
When you get hit near the edge, for example by Marth's f-smash, your trajectory don't send you into the wall at all.
At middle %, a simple ASDI towards the stage will make you hit the wall, as long as you aren't sent away too fast. It works just like how ASDIing down makes you stay grounded .
However, at higher %age, this won't be enough. Moreover, the more damage you get from the hit, the longer you'll stay in hitlag before you tech, which means a more difficult timing for pressing L, because those hitlag frames are removed from the 20 frames window for the tech.
Now, if you learn to press L and do a Smash DI around 15-20 frames later, the tech will be guaranteed :
Instead of waiting for hitlag to end and use ASDI to touch the wall, the hitlag will transfer into teching the moment you did the smash DI.
This is very easy : Press L, then slam the stick towards the stage. Regardless of what your opponent is doing, it'll most likely work.
As to what happens afterwards, the moment when you tech doesn't matter, everything will be as if you only teched at the end of the hitlag : you will start moving again at the end of the hitlag and you'll still have invincibility frames then.
I think that using smash DI also makes wall-jumping easier since you have more time (the remaining hitlag frames) to press up on the control stick.
Teching isn't button mashing :
In order to tech, you have to get a precise timing and not resort to button mashing.
Whenever you press L, it enables you to tech in the 20 following frames, but it also prevents you completely from using L to tech again in the following 40 frames.
It's not obvious, but it's very important when you're being comboed.
Has it ever happened to you, when you're being comboed,that you missed a tech even though you pressed L at the right time ?
This is the reason it didn't work. You had pressed L earlier and you didn't wait enough time before pressing L again to tech.
Note that if this happens, you can keep missing techs.
A guaranteed way to miss every tech is to press L too often, like twice per second.
When you're comboing, listening to your opponent's controller can be useful in some cases. Sometimes you know he won't be able to tech the following move of your combo.
Also, L-cancelling involves pressing L so you may want to learn to L-cancel without pushing the shoulder button the whole way (it's unnecesary), or to L-cancel with Z.
Just in case.