Would it be of any help if we swap the 16" squeegee blades for let`s say 17" blades. That would mean they stick out on both sides by 0,5 inches as the squeegee holder would still be only 16" wide.
I'm going to say no on that. It's not good practice to use squeegees that are wider than the pallet.
These are the three main reasons:
1 - You will likely generate lines on both sides of the image at the corners of the pallets. When the squeegee presses the garment into the corner of the pallet, it causes this ghost image. I've heard it referred to as die migration. Perhaps someone here can elaborate further.
2 - The squeegee rubber blade is being misused and when it's back trying to do a 16.5" wide stroke - there will be apparent print degradation on the outsides of the image.
3 - It causes inordinate mesh wear. - As the mesh is being deformed over the corner of the pallet it's weakening the mesh.
Just my 2 cents -