Don't do the BOJ's work for them

I might have to keep a running list of Do's and Do not's today ;-)

The BOJ only needs to do half the job. If and when they do intervene there will be so many others jumping on the bandwagon that they'll extend the BOJ move by probably 20-30%

Don't be one of the suckers who jumps in when you see "BOJ intervenes". You'll likely be late and you'll likely be last and end up long at a possible top. You may well get some good profit but your risk will be huge and that's not something I would be happy with trading.

If you happen to be long and catch an intervention then take the money and run but remember that's a bonus and not a plan (unless you're long explicitly waiting for intervention).

Lastly (for this post anyway) you also need to pay heed to other pairs that have the intervention Sword of Damocles hanging over them (CHF, NZD, (AUD to a lesser extent)). For one, there's likely to be reaction from people who put two and two together and come up with five that intervention in one currency leads to intervention in another. While that's not necessarily true there is scope (as Mike wisely pointed out in his post just now) that other central banks with fingers on their triggers will be on alert, if only to make sure there's no untoward fallout for their currencies.

We're in for some fun (and dangerous) times indeed so I'll repeat, make sure you have your positions under tight control and there's nothing wrong with leaving it all alone and trading something else. You don't want to see all your hard work count for nothing.