How to handle Blank Cells when using SUMPRODUCT(), SUMIF(), and INDIRECT()

[RAF43]

Hi All -

I'm working on a project that has a number of worksheets structured like below. It's a design that can not be changed. I'm not quite sure how to handle the blanks below the names. I'm wanting to sum for columns C & D on a summary sheet, including all the blanks until another name appears.

For example:
On the summary sheet in column B2 returns: =SUMPRODUCT(SUMIF(INDIRECT("'2'!B5:B28"),$A6, (INDIRECT("'2'!C5:C28")))) returns 1. I want it to return 5 and sum all the blanks below the criteria (A6) name on the summary sheet..
On the summary sheet in column C2 returns: =SUMPRODUCT(SUMIF(INDIRECT("'2'!B5:B28"),$A6,(INDIRECT("'2'!D5:D28")))) returns 0. I want it to return 4 and sum all the blanks below the criteria (A6) name on the summary sheet..

On the summary sheet in column B3 returns: =SUMPRODUCT(SUMIF(INDIRECT("'2'!B5:B28"),$A7,(INDIRECT("'2'!C5:C28")))) returns 2. I want it to return 8 and sum all the blanks below the criteria (A7) name on the summary sheet.
On the summary sheet in column C3 returns: =SUMPRODUCT(SUMIF(INDIRECT("'2'!B5:B28"),$A7,(INDIRECT("'2'!D5:D28")))) returns 1. I want it to return 4 and sum all the blanks below the criteria (A7) name on the summary sheet.

So in other words, how do I get it to sum for the blank cells below the name ... until another name appears ? Any ideas how to best tackle this one ?

Many thanks -
Randy

Summary Sheet returns the following from below worksheet structure

Name	Lab	Lec
John Doe	1	0
Jack Doe	2	1

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</tbody>

Date	Instructor	Lab	Lec
4/21/2013	John Doe	1.00
		1.00
		1.00	2.00
		1.00	2.00
		1.00
4/22/2013	Jane Doe	2.00	1.00
		2.00	1.00
		2.00	1.00
		2.00	1.00

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