I haven't seen the Heartbeat article but I can tell you what has worked for me. This is my 5th year raising deer and for the first 3 years I bottle fed half my fawns and by the time I weaned the bottle fed fawns, the mother raised fawns were eating apples out of my hand and most of them let me touch them. The mother raised fawns were also larger than the bottle fed fawns.
This is how I do it.....When the fawns are born I wait til they are cleaned off and nurse for a while and then I do vaccines and ear tag. Then I take the fawns into the fawn pen that is attached to the birthing pen but i have a piece of plywood 2 feet high that keeps the fawns from getting in the birthing pen but the mothers can go back and forth to feed fawns. I have a birthing pen and fawn pen. I raise the plywood as they get older. Everyday that I can, I touch the fawns and for the first few weeks I will stimulate them to go pee and pooh. I will also sit on a bucket in the fawn pen for at least ten minutes a day. As they get older I give them treats and by the fall they are perfect for handling. They are tame but not "stubborn" tame.
I don't think this would be called "imprinting". I would call it fathering the fawns because I'm not replacing the mother but I'm changing some of the diapers, giving some treats and spending quality time with them...lol
This is something that has evolved into what it is, I didn't plan for it to work like this but I am sure glad it did! I will never bottle feed again unless I have to. -Dan