I was also thinking along those lines MollyMay, very often the Rector would hand those notes/scraps of paper to someone else to write up in the PRs, providing the opportunity for errors to creep in. What made me think along those lines was that I've seen Jos and Thos written in the PRs and be darned difficult to decipher which they are. Some years ago I saw a post by a lady with a deceased relative who was a Vicar/Rector or similar, in his pockets were scraps of paper being notes of baptisms, marriages and burials, none of which appeared in the Parish Registers.
Having seen for myself some of those parish register originals I'm in your corner with that. Have corrected some original transcriptions also, & had 2nd thoughts about some which are still there in abbreviated form. Bts at times vary from PRs.