You're picturing your and your friend's applications as like two horses, racing. This is misleading. Your two lots of paperwork are part of a sea of tens of thousands going through INZ's hands at the same time, getting pushed along by currents of workload and redeployment and people being on or coming back from their holidays, newly trained and experienced staff... All INZ engages for is to process each application, not for a parallel path for them all. When it comes to a work visa, there are more factors which have to be verified, and every person's situation is unique, so there is even less chance two work visa applications will take the same amount of time.