Well, de Gea has been here for a year and a half, so this extended period of time thing you keep banging on about, he hasn't even been at United for an extended period of time. Unless you make up a random time span just to cover your tracks. It's obvious he is improving, yet you seem more interested in slating the kid rather than looking at the positives. Ivanovic has proved himself, because he's been at Chelsea for over 5 years and is a mainstay in the team. De Gea had a career before United, where he was known as one of, if not the best young keeper in Europe. Why do you think so many goalkeepers current and past think the same? Give him a few more years before you try write him off completely and put every goal we concede down to some non existent error you see in your head.