z-transform entry and the whole filter maths thing

[p2409]

I've recently been trying to learn about filters and DSP in general.
While there are heap of tutorials out there on the maths behind DSP and filters, I found myself continually missing some of the basic concepts. The issue for me personally was few of these tutorials ever mentioned 'why' you choose to do things like z-transforms in any detail - lot's on the mechanics, almost nothing on the reasons. (btw The best 2 paragraphs I ever read on this whole topic were here in KVR from Ecko - search on z-transform)

I have made an entry in the Wiki on z-transform with the 'why' bits in relation to music emphasised, but I don't know I have it right.

So...
a) can anyone comment on my z-transform entry in this Wiki - I'm sure I've got some of it wrong
b) do others yearn for this kind of explanation ie. the why's and the application of the maths to sound with worked examples as opposed to pages of symbolic maths?
c) Is it worth continuing this effort in this Wiki or do people think this is best left for the specialised tutorials offline?

[Ben [KVR]]

Link : http://www.kvraudio.com/wiki/?id=Z-transform