I would really recommend you look at your husbandry because chances are the reason your snake only eats once a year is something correctable. I also would never feed that many rodents in a feeding and it's best to wait 10-14 days in between feedings to let the snake digest. Otherwise you are really risking serious issues, regurge or all that food rotting inside before it's able to be digested. I'm not clear on why you would think live feeding can't be dangerous simply because it hasn't been dangerous to your snake yet?