It's not just the communion in the hand, but it's the communicant saying "Amen" to the phrase "Body of Christ". Even the GIRM describes this as the communicant's assent. Well, Catholic theology has never said that the eucharist is the Body of Christ when the communicant approves. And the GIRM describes this procedure as "honoring the communicant as a member of the community".
Well, Catholic theology has described the Blessed Sacrament as receiving the Body, Blood, Soul and Divinity of Our Lord Jesus Christ. By receiving this sacrament worthily, we are on the receiving end of a Heavenly gift.
If you receive a Heavenly gift by eyeing it and then saying, "Ok, it's acceptable to me." That is insolence. And it's in the GIRM which means its rubrically approved.
The novus ordo, being a blend of protestantism, also blurrs and omits Catholic doctrine.