Your observation IS a major concern. Do you think that McCarthy will try to push his minimal weight around to remove the pro-life plank?
Not by himself, but he can do things with the committee rules, membership, procedures and such to give their side an edge. These people are very sharp on strategy and parliamentary procedure (though not as smart as might wife who used to run circles around them). In fact Kevin himself can purport to be opposed to the anti-life efforts, but only the insiders will be able to see how he will assist them with every move.
Like I said I've been crossing swords with Kevin going back to the Young Republicans and College Republicans in the 1980s. Outside his own county he loses more than he wins, but he and his ilk keep coming back. Prolifers need to know that they CANNOT drop their guard when Kevin is calling the shots.