I am sending this question again, soon after I sent the question, I lost 
contact with the forum and have just now signed back on.  Still looking for 
an answer:

Question: Our company processes circuit boards in panel form, (eg. six 
three inch square boards forming a panel that will be six inches wide by 
nine inches long.)  The individual circuit boards are joined to each other 
with small webs, 0.25"long by 0.060" wide, separated by two to three inch 
spaces.  A shear is used to separate the individual boards from the panel 
after the wave solder operation.  Most of our products have been Type III 
assemblies, CEM1 board material, but we have also been doing Type II 
assemblies, FR4 board material for the past year.  Our problem is that the 
larger, multi board FR4 panels(0.060" thick) are bowing during the reflow 
process across the width of the panel by as much as 1/4".  The bow creates 
problems in the next operations of thru-hole insertion or SMT placement.  
The bowing appears to be compounded by the panels while they are in a 
magazine.  I feel that this is due primarily to the practice of using the 
webs to connect the circuit boards within the panel.  However, if the 
amount of web material is increased, we will have to switch from shearing 
to a routing process, scored panels or punch/return style boards(I hear 
that these warp also!).  Another option is a pallet, but this will affect 
the flow-thru process, non-value added labor, and increases tooling cost 
(we are a high volume shop).  Is there another method to eliminate the warp 
problem, or will FR4 material always warp in the reflow process, if so by 
how much?  Is there a panel width, with or without webs that the material 
will not warp?  I am presently planning to purchase a new reflow oven, and 
a center board support is another option.  I am using a standard reflow 
profile with standard soak zone temperatures, liquidous temperatures, and 
peak temperatures.

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