OK maybe I'm dense (it is quite late) but it seemed like the UDF returned in 100 lines what we had in 1. However, I made extensive changes to the UDF to get what I wanted. For any interested here is the result;

-- == Sample Code ==
--SELECT * FROM fn_SplitZ
--('?UID=N0464A&Section=Auditor General&Firm=GenDiesel&AI=Second',',')
-- Returns:
-- Col1	| Col2
-- UID 	| N0464A
-- Section 	| Auditor General
-- Firm 	| GenDiesel
-- AI 	| Second
-- == END Sample Code ==

-- Fn_SplitZ() Function 
-- Joe Johnston 03:30 10/17/2002  
-- This code loosly emulates the VB Split command

CREATE FUNCTION fn_SplitZ(@sText varchar(8000),@sDelim varchar(20) = ',')
RETURNS @retArray TABLE (Col1 varchar(8000), Col2 varchar(8000))
AS
BEGIN
DECLARE @Col1 varchar(8000),
	@Col2 varchar(8000),
	@bcontinue bit,
	@iStrike smallint,
	@iDelimlength tinyint

IF @sDelim = 'Space'
	BEGIN
	SET @sDelim = ' '
	END


-- Clean up our input string with a little code from Carl
SET @sText = LTrim(REPLACE(REPLACE(REPLACE(@sText, '?',''), '=',',') , '&',','))+@sDelim
-- Set initial length
SET @iDelimlength = DATALENGTH(@sDelim)
-- Out loop control var
SET @bcontinue = 1

IF NOT ((@iDelimlength = 0) or (@sDelim = 'Empty'))
	BEGIN
	WHILE @bcontinue = 1
		BEGIN
		--If you can find the delimiter in the text, retrieve the first element and write it
 		IF CHARINDEX(@sDelim, @sText)>0
			BEGIN
			SET @Col1 = SUBSTRING(@sText,1, CHARINDEX(@sDelim,@sText)-1)
				BEGIN
				INSERT @retArray (Col1)
				VALUES ( @Col1)
				END
			
			--Trim the element and its delimiter from the front of the string. Increment the index and loop.
			SET @iStrike = DATALENGTH(@Col1) + @iDelimlength
			SET @sText = LTrim(Right(@sText,DATALENGTH(@sText) - @iStrike))
		
			END
		--If you can find the delimiter in the text, retrieve the Second  element and write it 
		IF CHARINDEX(@sDelim, @sText)>0
			BEGIN
			SET @Col2 = SUBSTRING(@sText,1, CHARINDEX(@sDelim,@sText)-1)
				BEGIN
				UPDATE @retArray 
				SET Col2 = @Col2
				WHERE Col1 = @Col1
				END
			
			--Trim the element and its delimiter from the front of the string. Increment the index and loop.
			SET @iStrike = DATALENGTH(@Col2) + @iDelimlength
			SET @sText = LTrim(Right(@sText,DATALENGTH(@sText) - @iStrike))
		
			END
		ELSE
			BEGIN
			--If you can’t find the delimiter in the text, @sText is the last value in @retArray.
			-- We have left this in case of a Param='' case.
			 SET @Col1 = @sText
				BEGIN
				INSERT @retArray (Col1)
				VALUES (@Col1)
				END
				--Exit the WHILE loop.
			SET @bcontinue = 0
			END
		END
	END
DELETE FROM @retArray where rtrim(col1) = ''  -- Clean up any left overs 
RETURN
END