The_Ed wrote:By weight would mean that the number of switches we receive could be less than what we ordered.
Only if you do it wrong.

The_Ed wrote: Just make a 10 x 10 board with mx sized pockets in it. Grab handfuls of switches and rub them across the board. When all 100 pockets are full you dump them in the appropriate pile. That's how you count 100 switches accurately in less than 15 seconds. This method is used to count and sort out defects in manufacturing.
For amounts less than 100 you just rub them into the appropriate part of the grid. Like for 41 you would rub them into the top 4 rows plus 1 switch on the 5th row.
I do see how your idea would work as well. As long as you take care not to damage the pins on the switches (I have no idea how sturdy/weak they are, so this might not be a problem).
I would probably use LEGO's

to construct the grid board, if I would use this method.
My weapons of choice though, would be an accurate kitchen scale and a calculator.
[Edit] Hehe, I was too slow. 7bit beat me to the punch. [/Edit]