two things, firstly, please do not use bright fonts as these are unnecessary.
secondly, some of your pros and cons are incorrect, for example, getting focused is not a bad thing, as shyvana was designed to take damage, especially when you chose to pick up warmogs, FoN and Thornmail.
that is reasoning behind down voting your guide.

looking good. a lot of work put into this, working on mine atm.

Ok, I'll explain, although I thought it would be obvious. Basically, high crit is good on everyone, but is it worth it on everyone? No, not one bit. Why is it not worth it on Shyvana? Because of her skills, she has a skill that lowers someone's armor, she has another one that is basically a super-beefed up critical attack, and a damaging aura that basically never stops and scales wonderfully late-fame, as opposed to another early OP AoE damage spell that does a very poor job late-game. I'm talking(in case you haven't guessed) about Garen's Judgment. Burnout is just as dangerous at any time of the game, and the damage it continually does, Shyvana being able to auto-attack too when it's on(unlike Judgment and just like Corki's Gatling Gun), eliminates the need for critical strike chance, leaving open possibilities for building tanky and balanced. Of course you can make it work with high crit, if you really want to, but usually that's the way you build guys like Tryndamere or Master Yi, who are almost(if not completely) reliant on their auto-attacks, seeing how their skills are only there to offer utility, not damage(obviously not the case with Shyvana). That way, all she needs is AD, ATS, and life-steal. These things can be found in two items: Bloodthirstier and Black Cleaver. Just the two of them fully meet Shyvana's needs, and even complement her skills, Black Cleaver essentially doing the same thing that Flame Breath does, multiple times even. This means that your opponent will basically be taking your full damage, as if he wouldn't have any armor on. We all know that true damage is better than double damage which gets reduced by armor, which in many cases opponents build a lot of, being very afraid of Shyvana(and strong melee fighters in general).

Of course, 30% ATS bonus just won't do, we need more, where do we get it? From another item, of course. Should that item be Phantom Dancer? No, too expensive and too offensive, we need a hybrid item, one that gives defense too. What else does Shyvana need? Magic resistance. So we need an item that gives MR and ATS. There's just one in the entire game and it happens to be on the items that Riot recommends for her, lucky coincidence, wouldn't you say :)) ?, Wit's End, an item which appears to have been tailor made for Shyvana(I basically never used it on anyone else). Sure, it only gives a 30 MR bonus, but giving the fact that you have Mercury's Treads and the awesome bonus from Dragon's Descent, it's all the MR you'll ever need(in 99% of games anyway). The on-hit magic damage isn't so bad either, as it'll force opponents to invest in MR too(as if Shyvana didn't do enough magic damage already). It' very cheap too, why wouldn't you want it?

I wouldn't say Sunfire Cape is mandatory but it is an item that most people use and for good reason. It fits Shyvana like a glove, complementing her Burnout quite nicely. Many people say that the damaging aura is useless, but on Shyvana, who already has one, it's like getting another point in it, as if level 5 of Burnout wouldn't be the cap. Also, since we already established we don't need the Atmog pair, we replace Atma's with it. Gives the same armor and 450 health, which paired with Frozen Mallet it'll give almost the same amount of health as Warmog's(problem solved).

Another thing, if you really want to base your Shyvana on crits, your build should have to contain Infinity Edge too, only then the investment will pay off. 48% critical chance means that just 1 out of 2 or 3 attacks will be a critical, it's basically a shabby job, not worth it on bit, without Infinity they won't even do 250% damage. Armor reduction is a much better idea, as buying Infinity Edge is not only extremely expensive, it also detracts Shyvana even more from being tanky enough to not die first in a team-fight. If this doesn't convince you that critical hits are NOT for Shyvana I don't know what will.

@madalin What the heck are you talking about? You don't explain why High Crit Chance doesn't work on her. Also, what MR item would you suggest, and why do you think Sunfire Cape is necessary?

High critical strike chance? And Atmog's? Really dude? I know she's Jarvan's girl, but not Jarvan himself. Such a build is good on someone like him, Garen or Olaf(I played the first two a LOT). Shyvana just wasn't thought out like this. Sure, she need ATS, but Phantom Dancer is NOT the way to do it, she needs to be tanky, but not just in health, she needs MRtoo that's why Warmog's should never fit on her, especially if you're a jungler. You get beefed up with FM already, Warmog's is just redundant, definitely a -1. No Sunfire Cape either? Just NO.

This should definitely be the top rated build. Have you seen the current top rated build? Most of the damage is AP damage. Definitely not how Shyvana is supposed to be played. Your build is excellent. Just a few questions. why not max Twin Bite before Burn Out? About the runes, why are glyphs of shielding preferred over glyphs of warding? Shyvana needs the early MRes. Also, why not Quints of fortitude, which give 78 hp at the beginning of the game? Or even Quints of vigor, since they give more health regen than Quints of regen until level 10. I'm not saying your recommendations are bad, I just want to know the reasoning behind them. BTW, have you tried the new summoner spell Surge? combined with Exhaust, Shyvana becomes absolutely op for 12 seconds from level 1 onwards.

yeah, great build, i love it! :D

Love this build!
Shyvana should be played as tankt/dps like this guide! Brilliant 1+ to you man!

@Fictionized I think you will find more why.
@ManaMiser I added a new section called "Situational Items" if you want spell vamp, go ahead, just be careful with taking out her defense.
@Tyus23 I think I will go will armor penetration runes, I see what you mean. Feel free to use my build in a different order as well, I just enjoy the early tanky benefits from Phage and Frozen Mallet. Don't dislike the guide because of the red runes, feel free to manipulate it to your preference if you wish.

I think your build is different and new over others. However, I do question it at the same time, even though it does work. But I think that you could use a bit more clearer explanation. Heal and other spells, just no? Why? Why shouldn't you take that? Karthus can take Revive, why not Shyvana? You should go into details a bit more, even if people do have the common knowledge you expect them to have. Because I personally don't see why Cleanse would be -such- a bad summoner spell for her.