Odd/Even teeth in bar?

[ctpres]

Markham about to build one for my 60" fel. Understand that usually means 5/odd number of teeth or one in dead center of cutting edge. Since I plan to lift things and put hitch ball in center for dumping trailer, should I add or subtract one tooth to free up center? Planned major use is digging and moving lots of dirt.

 

[carpenter383]

Why can't they just set the tooth spacing to where the center is left open, but the teeth are still all the same distance apart?
Something I've always wondered about tooth bars is why are the teeth upside down?