Yeah, but no, but...Does this correspond to rear-curtain flash?
I recall Syl Arena stating that shutter speed controls the ambient exposure and aperture controls the flash exposure.
So I can use the 'Dragging the shutter technique' using either manual or TTL flash according to Mr Neil Van Niekirk, Would that be correct?
Yes.
If you start by thinking that your flash exposure and ambient exposure are 2 separate things that combine to create one image it helps you get your head round what you can and can't do with flash.

Phil once again you've hit the nail on the head! Thats where the problem lies I'am not sure what I can and cant do with flash!
Are there any decent books/websites out there that could help me?
It's the use of a slow shutter speed to balance ambient exposure with flash.
Speedlighters Handbook[/URL] by Syl Arena. Half an hour with that will have you sitting there saying 'Course it is, why couldn't I work that out'.
Thank you, It's a pity it's predominently/exclusively about canon speedlites!
Anything about nikon
So really, it just means using the correct shutter speed.
I have never understood why it is referred to as dragging.
Steve.
There's no such thing as the 'correct' shutter speed Steve
What an interesting site...lots to read! Neil van Niekerk: Index of Articles, Rough Guide to Tangents and his main blog.