Drywall Priming

Unless I’ve missed it, I don’t see where you’ve addressed the subject of drywall “texturing”.

Question: I’m currently in the process of getting bids for a drywall job in my shop addition. Two drywall subcontractors have given me bids, both of which include an application of drywall primer PRIOR TO the application of the orange peel texture. I don’t understand why anyone would prime the new drywall BEFORE the texturing instead of AFTER the texturing so that the texture is sealed along with the drywall and the mud. When I questioned one of the subs, he e-mailed me that “the reason for priming before texture is to seal the surface so you do not get any “flashing” where the mud on the seems is”. I have no idea what “flashing” is or what he means. Sounds to me to be more likely that they’re just trying to soak me for a costly, unneeded priming job since I’m going to then have to go back after the texturing and prime it all over again. Can you tell me if there’s really any reason for this? Is this some sort of gimmick the drywallers use to help cover up their less-than-adequate quality in the finishing stage?