Haven't read all this thread but.
FOR GOODNESS SAKE! I have just finished a course taught by HV's about BF who would regard that kind of advice as total rubbish, or a last, extereme resource after all else has been tried AT BEST. It it so annoying whhen you get these HV's floating around giving outdated advice.
BF friendly advice would be for you to instigate feeds every two hours, thus giving plenty of opportunities for baby to have lots of milk and building up your supply.
As long as your positioning is OK (no soreness etc) and you are getting through 5-6 wetr nappies a day and your baby is putting on weight don't worry.
Find out who your local breastfeeding support crew are go to them if you want reassurance. Please, please, please don't let ignorant, outdated advice from somebody ruin your breastfeeding relationship.
It is hard to balance formula feeding with breastfeeding because it artifically stretches the baby's tummy (making breastfeeds less satisfying) and reduces supply by interupting the sensitive supply/demand system. Although some women mange it, for most, introducing formula more often than not puts mothers on a path that finishes BF altogether. Fine if that's what the mum wants or would be happy with, but you clearly aren't and frankly it is a disgrace that you were given such poor advice.