If a parishoner's heartrate gets above 80bpm during the "melodies in the heart" portion of the service, I think we can assume that the parishoner is lusting in his heart rather than singing melodies in his heart.
If only heartrate monitors were permissible in heart-singing worship, then we could separate the wheat from the tares. But alas, they are not mentioned so they must be prohibited.
Another thing not mentioned was the baptismal pool that many churches have (ours does) inside the church house. Jesus was baptized in the Jordan River, and they used the Jordan River for baptizing a lot back then because there was much water there for that use. Having it inside, on second thought, since not mentioned specifically might just be . . . well, forbidden? illegal? . . . Nah.