If you get chaingrabbed from say... 1/2 to 2/3 of the stage and the Falco does it PERFECTLEY, you're basically screwed if the Falco chaingrab spikes you and then grabs the ledge. If he spikes you offstage anywhere after 40%, there's no way you'll make it back to the ledge without Egg Tossing, but you'll only make it to the ledge at the least and Falco will be hogging it, so your only hope at that point is to hit him with the Egg Toss while avoiding his invulnerablity frames.
Yes, those ****ing lasers are annyoing and they block out nearly everything that we try to do, but there is something good that can come of this. If you manange to eat lasers to 40% you can rest knowing that you won't get chaingrabbed to oblivion, but the fight is just starting now. :edit: Basically, after you get blasted/take damage up to 40%, you have get to go in and fight without any worries of getting chaingrab/chaingrab spiked. However, once you get in, you need to to STAY IN. Letting Falco regain his advantage will take us like another 50% until we can get ours back. So, once you get in, we need to stay on his ***.
Even in close combat, it won't be easy. Falco's jab is like 3x faster than ours. What's even worse is that it has a rather wide range as well. That ftilt has a pretty big range too. The solution I've come up with this is: Initiate that jab-crouch-jab-crouch thing against Falco (speaking more so at higher percents). What'll happen is that Yoshi's jab will come out just as fast as Falco's and it will clank, but keep doing it until it hits. Eventually, after about 3-4 hits, Yoshi will be outside of the range of boat the jab and Ftilt, but Falco will be within range of Yoshi's Fsmash.
The playing field gets set in Yoshi's favor whenever you grab Falco. When you grab Falco, make sure that YOU KNOW he can't avoid it. Missing that grab will result in Falco dodging it and you getting grabbed or eating a down smash and thus setting the playing field in Falco's favor all over again. Now you're stuck trying to get passed those blasted lasers all again. When/if you D-throw him and want to follow it up, Falco will probably beat you out of it with his D-air. You can bait this and punish it from the ground with a Uair or whatever you decide to do. Using Ftilt probably isn't the best idea either out of Bair. You'll be much better off using Utilt since Falco can't grab that as easy. Buffering the Chaingrab is a good idea, but missing is not. You also do not want to do this on a stage with relatively low platforms such as Battlefield.
When offstage....As much as you REALLY don't want to be high in the air at a high percentage, your only hope is to anticipate his rising Bair/Uair, dodge it and land on the ground safely and continue to play it safe and hopefully make it through. When coming on the stage from below however, you HAVE to be mindful of the F-tilt and F-smash. Both of which **** Yoshi pretty ****ing hard to say the least, if you get hit with either one, you're dead so be careful when doing this. If you can grab the ledge and Egg camp and work your way up, Falco won't have time to pull off either move. If he's close enough you can enter the stage with a rising Egg Lay, but you have to be fast and unpredictable about it though or you're just about as good as dead. :edit: If you are below the stage, I would advise NOT throwing an Egg. Doing so will get you jabbed then edge hogged. He can also grab you out of your second jump and then you're really screwed.
When Falco is offstage, he can EASILY be gimped with correct timing via Egg Lay, Dair, F-air spike etc. You can predict where he will land from his side-B and **** him with a F-smash if he lands in front of your face on the stage. Yoshi's Nair cancels out the phantasm as well. If you time it right, Yoshi can jab Falco out of his double jump return for the ledge. Honestly, it'll take AT LEAST 1 second for the player to figure out what just happened. So, depending on how far down he falls after the jab, will determine what you should do next. If he comes back with the Fire bird, just edgehog him. If he's able to return with the Phantasm, Nair him until he cannot return. 2 Nair's should do the trick, but just make sure you can return yourself.
Egg Rolling is only good for keeping him in the air after throwing him in the air. Other than that, you really shouldn't use it much. If at all.
Getting in close and getting Falco off the ground is the key. Using Usmash is great for punishing any bad spotdodges or if we get a lucky jump imbetween the lasers. <3