All edginess aside there are a few logical things to look at in seeking a answer to this question.
1. The ATA rule book is a good place to start for verification and is easy to get a copy or check online. www.shootata.com
2. Take a look at Browning and see how many Citori--XT--725 model trap shotguns they manufacture for the sole purpose of
shooting competitive trap.
3. There are many that do not like porting or see a use for it ect. but porting is a part of shotgun culture and standard on several
brands so I think it is here to stay.
Good luck with your sporting clay range, I think that if you talk to several of your customers that shoot both Trap and Sporting
you will find that they are welcome at the trap ranges.