DSLR speedlight continuous shooting?

I recently got into on camera flash photography. I have a SB-600 w/ Sto-Fen diffuser on a Nikon D5000. I found out that if you use 1/1 (full power) it takes long time to recycle and 1/64 you can take many many pictures without recycle time (continuous shooting up to 6 fps, about 4 fps on D5K at 1/125 to 1/200th). I want to know if I can take continuous pics with this and what power I should set it on on M mode. 1/64 can take a lot of pic but it is weak and not enough to expose the subject right. So is 1/32 or 1/16 good enough? Because I see on TV news photographers are really good at it. And they probably use SB-900's or Canon equivalent and it has more zoom. The SB-600 only go up to 85mm (FX) so does that mean if I use a zoom lens at more than 85mm the flash won't cover the whole view?

Added (1). Yes i have a fast lenses, 17-50mm 2.8 and 50mm 1.8.

Added (2). I only intend to use continuous flash sometimes and for maybe just 4-8 pictures.

Reporters tends to use the 800 or 900 flash, often with an external battery pack.

With any flash sooner or later the overheat protection will cut in and temporary halt your flashing frenzy.

Speedlights are not really intended for continuous shooting - at least not at the consumer level.

What you are going to need to do is buy 64 speedlights. Set them all at 1/64th power, and find a 2x4 to mount them on. When they all go off, collectively they will output sufficient power.

Then you will be able to continuously use the flash units.

Or better yet, learn to use your camera with continuous shutter mode turned off.

Or look into buying a Quantum flash.

Yes, lower power output means faster recycle times. Like with everything in life, there's always a tradeoff.

Many flashes can't do continuous shooting indefinitely. Some need to rest for a few minutes after a certain number of consecutive flashes (even at low power). I have one such flash. Read the manual that came with your flash, as that will tell you.

Also, it's important to distinguish between a flash shooting at the same frames per second as the camera, versus pressing and repressing the button quickly with flash (in that case the flash does not shoot at 6fps or 4fps or whatever, it shoots as you are pressing the button every second or so. Which is still fast, and is a good way not to overload your flash). That's what I do. It also helps if you have an external battery pack (lower recharge times).

Your flash manual will tell you how strong your flash is (the coverage will depend on the power and on the zoom you are using). I think you are confusing 85mm with the guide number of the flash, which will vary with the zoom (there should be a guide number table or something similar). Those tables can be a bit confusing so best bet is to practice and make a little cheat sheet of commonly used f-stops or how far you subject usually is.

take home message - read your manual