Tanking made easy(er)

For protection warriors out there, soz bears and pala's but i understand threat generation for you is pretty good already anyway.
I've been tanking this week on my alt again for a change and this weekend i got an idea suddenly, while in bed ofcourse as there is where most good things are created.

As you might know some skills provide better threat then others, others are more rage efficient and others you mostly use when you have plenty of rage to spare. This gives a certain order of skills to use as you will have to deal with cooldowns, which results in a threatrotation or threatcycle.
The best skill is Shield Slam which gives the best threat, then Revenge which has the best threat/rage ratio and then Devastate, again rage wise.
As Shield Slam is the best you want to use that every time it's up which is every 6 seconds. This results in the next threat cycle:
Shield Slam, Revenge, Devastate, Devaste > repeat

In the past i experimented with a macro for this: /castsequence reset=6 Shield Slam, Revenge, Devastate, Devastate
However, such a macro is easily messing up your threat if there is some delay in your cycle due to using other skills in between or simply lag.
So what did i come up with?

/castrandom Shield Slam, Revenge, Devastate(Rank 3)

This macro uses whatever skill is up, starting from the left. The beauty is that you can start with this macro at any moment you want, do anything in between and still use the best available skill without having to worry about cooldowns or checking if you have enough rage.
But there is more...

/castrandom Shield Slam, Revenge, Devastate(Rank 3)
/cast Shield Block

Just spam this baby and it will use Shield Block when it's up aswell, this makes tanking a boss (you only need Shield Block on mobs that can do crushing blows) almost a 1 button experience. Ofcourse you can use other skills like Thunderclap, Commanding Shout and perhaps even Disarm aswell. When you go excessive rage you can manually use Heroic Strike for extra threat.. or use the following macro for that:

/castrandom Shield Slam, Revenge, Devastate(Rank 3)
/cast Shield Block
/cast !Heroic Strike(Rank 10)

Does the same as the previous macro but uses Heroic Strike aswell. If you get low on rage simply switch back to the previous macro without any threatcycle mess ups.

In the end i still would advise to keep all the original skills on your taskbar within reach, when tanking multiple mobs you might want do things a bit different for example. I myself often pull the 2nd target first and quickly devastate him before Shield Bashing the target which is going to dps'd down. This gives me a nice headstart and with a 2nd mob on you will be able to quickly get some decent aggro before switching to that 2nd target again. (taunt is for emergencies, not for grabbing a target on the pull)
Doing it manual might also be more fun (or less boring anyway) but for less fingerquick tanks (or when you have a bad night) this macro should do pretty good.
Truth told i haven't been able to test in a raid yet but when testing it outside i easily got over 800TPS with shield block and without even using HS.
When using HS i got results over 1100TPS and i'm just decked in Kara gear but i couldn't keep the cycle for long as i got serious rage shortage.

I'm hoping i can let you know just how good it works soon or let me know if you've had a change for it aswell.