The weight hole in the thumb quadrant removes excess thumb and side weight. If the ball has a large enough pin out, have the driller make sure that the layout allows you to use a weight hole in the thumb area. The larger the pin out, the easier it is to lay out these "double thumb" type layouts.
You can put a weight hole wherever you want to, as long as it falls within the static rules guidelines.
Remember that static side weights are meaningless, thus if you want to use a low weight hole in the thumb and this removes thumb weight, as well as side weight, the weight removal is meaningless. This allows you to even have the balls side weight be negative.
The low weight hole changes the shape of the core, thus how the ball rolls. The ending static numbers are just numbers.
You can use the thumb quad weight hole no problem. Just get the ball to legal specs and your good.
Edited by The Dreaded Durbin on 1/22/2011 at 9:21 AM