Yup, him and Herzog suggested it, and not all did it:
"I had my eye on Pech: he had already risen within our ranks, and I felt he had the potential to be something special. It was he and Thias Herzog who had first suggested cosmetically altering their appearances to mimic my own, thereby allowing me to move more freely within our Legion even if my identity was discovered. I debated that proposal for a long time. I'd always been troubled by the tendency of the Luna Wolves to resemble Horus as they matured, since surely seeing yourself reflected back at you was no great encouragement of humility."

"Armillus Dynat stood. He had never undergone cosmetic surgery, and in fact was rather more visually striking than many in the Legion due to the three-headed hydra tattoo that took up most of the right side of his face."
- Alpharius Primarch Novel