Ok, I may have been overexaggerating earlier about Iike being unplayable without throws(though I still feel he'd be awful), but without Jab he truly would be a joke. Nobody who uses Ike has to be told this. Sadly, though, a lot of Ike's go about using Jab incorrectly.
Firstly, if the first 2 hits of jab are blocked PLEASE do not do the third. Why? Well, there's this little thing call sidestep, and it's extremely easy to step the last hit and leave Ike wide open. Doing the jab series again after it is blocked or sidestepped can trick people sometimes, but it's best not to depend on that.
HOLD Jab instead of tapping Jab. This makes the jab combo come out at maximum speed all the time without having to worry about tapping and make it slower in between each hit(making it easier to interrupt). Holding also makes letting go upon seeing it blocked or hit much more reliable.
Holding back also works so well because of Brawl's jabbing engine in general. If a character is floating slightly off the ground, Jab will continue to reset to the first hit until the engine believes the 3rd hit can connect. Because of this you can have a lot of 1,2 1,2 1,2 1,2,3 series with Jab. Hold...don't tap. Can't stress that enough.
Jab is your ultimate punisher. Block anything fast enough that none of Ike's slower attacks can hit? Jab. These include sword dance by parth, Snake's forward tilt, Snake's jab combo, missed throw attempts, Samus' dair, whatever.
Jab has great priority and interrupts a lot of things. Upon fairing, nairiing, etc and having it blocked, sometimes jabbing is a good option against overall aggressive opponents. I can't even count the amount of times opponents have just ran into it.
Jabbing right outside of hitting range keeps defenses honest. From this you have many options? They keep blocking? Dash in and throw, dash in short hop back nair, etc. If you feel they are going to go in for an attack, short hop back fair. Use your head pretty much.
As everyone knows, after a whiffed quick draw, Jab is a great follow up. Be wise about this and try to read the opponent and their spacing well to maximize this use. QDing into Jab can allow you to mix up QD into throw if the opponent tries to just block.
Jabbing is anti sidestep for the most part. Someone is going to sidestep you? Holding jab in their face. More times tha not Jab is going to eat them up if they try to do anything. I like to keep jabbing even if they continue to spam side step. Short hop nair out of jab spam to beat sidestep is helpful too. It is semi flow, and can catch sidestep.
Jab on block is tricky. Like I said, if Jab is blocked it's best to stop after the 2nd hit(first hit if you ANTICIPATE jab being blocked). Single jab being blocked gives you some good options. Short hop nair BEHIND the opponent or away. Short hop away fair, grab, etc.
Jab is excellent for beating air dodge from right above the ground(like right before it can be cancelled into a shield). When ground stalking, look at when the opponent air dodges. Sometimes walking near them and holding jab so they fall into your jab combo right out of the air dodge is effective. They will be floating, too, so if you hold jab there's a high chance you wil lget the extended series. Doing this can cause the opponent to try to attack on the way down instead or air dodge. If you anticipate this, block, and punish with Jab anyway ^_^.
Jab on ground hit really opens up Ike's meta game. Single, or double Jab gives you lots of sexy options. Jab(or jab,jab) into throw is a staple. If opponent try to sidestep after eating too many of those, instead of grabbing after the jabs, walk up after them and hold it so that you can beat their sidestep. If they try to jump away or towards you with an attack to avoid it, short hop fair towards or away from them. It's all a matter of anticipation and reading the opponent.
Jab into nair is really sexy especially for the sidestep happy. Jab,jab, they go for sidestep? You're already in the air nairing(away from them preferably to increase the chance of being unpunished if blocked).
Jab jab on hit can give you some other sexy set ups that can really mess someone up who is too anxious. Jab,jab, forward tilt and Jab,jab,forward smash both can annihilate a mistimed sidestep or air dodge, or simply someone who's mentalitiy is, foolishly, that "I've been hit by the first 2 so I'm going to eat the third. I'm not even going to try to avoid the 3rd"...fail.
Jab canceling can be effective for those who don't go out of their away to avoid Jab once caught in it as well. Do this by jabbing once, then tapping down to cancel the animation, and jabbing again. If they don't attempt to intterupt the jab combo, you can extend your combo fairly long. Jab cancel, jab cancel,jab cancel, hold jab. Stuff like that.
Holding jab when edge guarding can be effective depending on who you're facing and what character they are using. Hopping back onto the ledge with an aerial can be ugly, but jab will beat many moves used for this. Holding jab to provoke a ledge hop, rising attack, etc can be effective. As SOON as you SEE or ANTICIPATE the opponent doing anything, let go of Jab and quickly short hop fair, forward smash, up tilt, up smash, or forward tilt. Whatever you use is dependent on what the opponent is going to do, so just be wise. Implementing fake/intentional jab attempts can cause Ike's already formidable edge guard game to become scary.
Jab, jab jab baby!
Mixing in a counter will throw your opponent off, though.
