Mira was never trained, also the racer spoke about more than likely was never trained...but free flown, there is a difference...
Mira grew with you, when he was allowed to fly he always kept you in sight...you were Miras home...same with Gem, none of my babies knew a loft as home, they knew a cage and the human, without the cage present they saw the human as there home...and still do...
When you train a bird to race, that bird only knows..."I gotta get back to my loft", when you free fly...that bird will learn his immediate surroundings never going far enough to loose sight of his area...or his/her loft, during training you are introducing the bird to new areas, the bird will fly higher to gain site of the area he already knows, and the release will go further out each time so the bird learns more and more.
Most Racers that fail to make it home as Basket Cullers, these birds have not been properly trained and are (unwanted birds) I have posted much information concerning the Culling ways of the Pigeon Racer to rid his/her loft of unwanted birds, then there is LOVE, some racers meet up with a fine little filly and (bye bye Race), also I have posted poems of the ways Racing People assure there bird makes it home, (she will fly faster to get home to her eggs), as the hen will be taken off her eggs and placed into a race.
The person that found the Racer with the wings clipped, she contacted the owner threw the band number, this person was a pigeon fancier, he free flew his birds, he may have raced a few he thought would be winners, however the most of his birds were not trained (cullers), when he decided he no longer wanted to stay in the pigeon keeping world he took his birds far enough away from there loft so they couldn't find there way home and released them and his birds found there way into Feral flocks and or perished during there search for food or they met up with bad luck and the preditor ended there life.
The clipping of the wings told me this one bird ended up in someones elses loft, this person knowing these birds can't be re-programmed clipped the wings.
If a Racer is chased by a Hawk-Falcon then all mapping is put on hold and its a survival issue, during the chase the bird frantically tried to get away and or look for a place to hide, this is where many Racing pigeons become injured (broken wings), they try to go through small openings knowing there chaser is much larger than them, or in a frantic turning to sharp...
All loft birds are banded on day four after birth, there's never a gimme (knowing the bird will be a winner), as the bird reaches maturity they are judged (standards need to be met before training), if these aren't met, its a quick snap of the neck or the bird won't be trained and entered into a race (basket culling), this is where the difference distances come in, first the one hundred mile race, and if the bird makes it home, then the training continues onto the 200 mile and so on.
We all know of cities and the mass poisonings, many and I mean many birds within a feral flock are banded, the Racing sport contributes to the feral population and hence contributes to there demise...this sport is anything but PRESTIGEOUS and frankly I think the sport should be obolished...
Hey....In there own words (the pigeon racer) its a world of Basket Culling and the quick snap of the neck....
& Camille sweetie...your Mira is half Dunn Lahore & Half Homing Pigeon...not Feral... 
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Both are Hybrids....
So...as I have always said, your baby will never leave you...NEVER...only the prediator or LOVE..can interfer...
Hope this explains how some Racers end up in feral flocks and or lost....Racers can (forget) there programming due to something happening along there journey..Storms-Winds-Preditors-Love....then its a life of wonder as they try and find there way HOME.....kinda sad huh?????
You all can help these birds....when someone says they found a Racing Pigeon, tell them its best to allow them to be free...don't try and find the owner as the bird will surely be killed if returned.
Free Flown Birds of Peace will always stay within a five mile radius of there home, Ferals will also stay within five miles of there birth place...
A Racer fails to find his/her way home, they wonder (forever) trying to find there way home.....if placed into a new loft...just as soon as that bird is released to free fly...say goodbye as there program now is to find there way home...the home where they grew up...unless they meet up with a feral flock and LOVE.....
Hopefully you all understand better now why I love these birds so much.
Take Care everyone.
Arty