Stefano (of Tango in Action) explained an interesting floorcraft myth recently at Negracha. Going against the line of dance is not in itself a problem - a giro goes against the line of dance for part of the movement. The problem is if the leader is going backwards without being able to see where he's going!
A huge problem with the way tango is taught to beginner leaders is that many sequences start with taking steps backwards. Simply put, doing this in freestyle is a very bad idea. At best, aware dancers will give you grace for being a beginner. At worst you're going to get impaled by Comme il Faut (and not necessarily by accident either).
Thankfully there's a few simple ways around this. From your start position / collect, step forwards with your left foot, but leave the right where it is. Now take a step backwards to collect your feet and take a sidestep left - see how you're in exactly the same position / dynamic as if you'd stepped backwards and sidestepped, without having to actually walk backwards into traffic.
Your second option is to again step forwards on your left foot and then take a step forwards on your right. Collect and take a sidestep to your left. This is basically the mirror image to what you do after the cross in the box step. Again it gets you back into your starting position. I prefer the first option simply because it's slightly easier and needs less room.
It's worth knowing that tango women are like knights on a chess board - it's easier to move them to step back, then right, then back, etc., than it is to move them continuously backwards or to the side. The obvious problem with this is that you drift over to the right and run out of dance floor. However by shifting between the above "forward - back - step left - do something", and "forward - step right - do something" you can weave a kind of sidewinder path along the floor.
It helps to think of a tango floor as either a river with eddies or as motorway traffic. Either way in some parts it's fast, others it slow. Some parts of it will even move in the wrong direction. It's tempting when someone comes flying towards you to freeze and tense. This is not a great idea. The dynamics of tango are much more circular and relaxed than Modern Jive. If you think someone's going to hit you, relax and try and step in a circle - most likely they'll miss or just brush past you. "Be the water not the rock". Hesitations are great for doing this. Incredibly easy to learn and lead, it's well worth asking a more experienced dancer to show you if you haven't learnt it yet. They also help you get around corners.
You'll also sooner or later find yourself with the follow's weight on her left foot, with someone charging in from the right side and you want her to step left. However she'll totally abandon her sense of self-preservation and stay routed on the spot rather than hop. All you need to do is pivot her. Doesn't matter which way, but now she can step to the left with her non-weighted foot - basically she'll either do the beginning of a back ocho or a forward ocho. Likewise if you want her to come straight towards you quickly because someone's about to hit her, don't stay straight on. There's a good chance she'll do something called a volcada which is basically a graceful trip. Turn your shoulders and she'll step with you.
Although it doesn't look it, tango is much less move driven than Modern Jive. Modern Jive teaches you more and more ways to move. Tango teaches you increasingly better ways to do the same movement. So while you may have fretted about only having 4, 10, 20, 50, 100... moves in your Modern Jive repertoire, in Tango you really are fine when you can lead the following - step forward, side, back and lead hesitations around in a circle. Sounds bizarre, but it works. Just relax and enjoy it and chances are she will too. Tango is much more about the connection. (The first time I tried this I spent 3 dances convinced I was boring the hell out of her, only to have her ask for another 3!)
If you look at the centre of the floor there's a quieter space, probably about 6 feet by 12 feet, theoretically for people to do fancier moves. A good way to practice tango in a Modern Jive Venue is to imagine that you're in that space. Don't try and go walking all around the outside of the room. It is possible but it's not worth doing twice...
- Christopher O' Shea