You hear what you want to hear right? You must be quite the person to have in an office environment. Mental. Arriving at Manchester United, making a name for yourself at United and around the world, leaving for Spurs in your early 20's, is career suicide. You will forever be branded as the guy that quit or didn't make it, you'll most likely never be playing for one of the greats again. Staying at United, outlasting Mourinho and/or proving everyone wrong is the opposite and his star will shine as brightly as it did two years ago. Furthermore, he would never spend time regretting his decision to leave during the next ten years.
Playing for Spurs is not career suicide, but again, you only constructed my message the way you wanted to, to be able to spout more crap for the sake of it - as usual.