Well, it’s going on anyway. I suppose you could refer back to outdated/outmoded information, and then have those conversations with your health care professional 
Wasn’t it thought to be linked to an anthrax vaccine, which was only available to the military? ISTR that.
To be very clear: if your kid is exposed to you they are exposed to risk. Pertussis exposure in particular is likely higher from adults, who have waning protection and little symptoms, than from other children in daycare, or siblings.
There is no benefit to a delayed schedule, neither known, no any rational reason to believe such. There is definitely increased risk associated with delays including to those children not in daycare and not having sibling exposures.
The data on safety and efficacy is most deep and extensive with the standard protocols that have been the subject of testing and have the most volume of real world use.
I mean, I’ve gotten lots of vaccines that were new since I was a kid. And my kids got vaccines that were better than the ones i had. There’s tons of advancements. But i just don’t think there’s much to be gained by fiddling with a proven schedule. They do test the schedule for safety and efficacy when new vaccines are introduced.
Hey, i was just vaccinated for pertussis last Wednesday, because my PCP said it was time. I didn’t bring it up, he did, probably because he got an alert when looking at my chart. I’d think parents of kids too young to be vaccinated would be on top of that. (I mean, parents who are vaccine-shy are probably not on top of their own vaccines, either. But if you are trying to do your best to protect your kids, you can get another dose of a vaccine you’ve tolerated in the past.)