Global form validation callbacks? Staged forms?

[eluser]tomclowes[/eluser]
Three questions today

1. I have a simple capcha check for usage with the form validation library/callack capabilities. I define my callack at the bottom of my controller. I want to use this callback function in all of my forms - is there a global location where I can define these functions?

2. I have a complicated 3 stage form. What is the best way of doing this with a controller?
At the moment I basically have a single function which uses lots of if statements to detect whether the form subit buttons of the respective pages have been submitted - is this the correct approach?

3. I had a break from development, came back to my code and thought WHAT ! I have commented everything well, so understand it again but it seems to me that splitting up things into M, V, and C makes it extra complicated to understand.. Views?

Cheers