Artemis BJJ (Bristol Sports Centre/MyGym), Can Sönmez, Bristol, UK - 26/11/2014
The americana is probably the simplest attack from mount you can do without a gi: the cross-collar choke is arguably as or more basic (in terms of the concept at least, the details can be complex), but that requires some kind of fabric to grip by the neck. Of course, the americana also works with a gi, it just doesn't depend on it.
To begin the americana, grab their wrist with your opposite hand. Grasp their elbow with your other hand. Keeping both of your arms straight, lean diagonally forwards, using your weight to drive their arm to the ground (as per the picture, you can also follow Cindy Omatsu's example and use your head to add further leverage). The elbow of your wrist-gripping arm goes next to their head. Remove the grip you have on their elbow, then with your palm facing up, slip that hand underneath their elbow. As it slips under, turn your hand so the palm faces down.
With the hand you just slipped under, grab your other wrist. This means you now have a 'figure-four' on their arm, a solid grip. To complete the submission, keep your head down and lift their elbow, pushing their knuckles back in a straight line along the ground, like a paintbrush. You want to move their knuckles, rather than pulling their elbow down as well: that goes up (but only slightly), their knuckles go back. Also, keep the knuckles in contact with the mat.
You can also vary your angle, which will affect how far you have to push their knuckles. For example, Saulo Ribeiro teaches sucking the trapped arm in to their body, then lifting the elbow. His angle is such that he doesn't need to paint the hand back at all. It will also vary depending on the flexibility of your training partner's shoulder. Finally, you can try twisting your fists downwards, like you were revving a motorbike. That should further increase your leverage.
I also went through the variation I like from super high-mount. If you keep going up, until you are right by their head, you can squeeze your knees by their arms. That should hopefully mean they have an arm completely stuck, poking out vulnerably from your legs. Simply put on a figure four and bend that arm against your leg for the submission. Be sure to use the turn of your body, rather than purely your arms: you'll get more leverage that way.
If they have managed to hide their arm, walk sideways on your toes to roll them and take the back. I tend to switch to technical mount for that, but you can also just walk sideways. They will end up flat on their belly, a position I find a bit irritating to manipulate, but it is still a dominant position (hence why it is so odd from a BJJ perspective that judoka go to there all the time, but that's due to judo competition rules limiting time on the ground. Judoka probably view guard pulling with equal disdain ;D).
Teaching Notes: As ever, I'm not sure if I'm adding in too much detail, but it doesn't take much time to go through the super-high mount version. Mentioning ways to increase leverage by using a more acute angle was good to keep in reserve for drilling, though there wasn't anyone there with hyper flexible shoulders. I'll have to try hitting the americana more often in sparring, although I tend to just take the back from there (which I showed briefly during drilling tonight as well).
Tracey brought cake (in her excellent Doctor Who lunchbox). Very tasty as always, lemon drizzle, I think. After the women's class and mixed class had got done munching, it was mostly gone. Thanks Tracey! :D