It sounds like you have a weird definition of what makes a club legend. Ole isn't a club legend because he was the best player in the squad, or in the league, he's a club legend because he was a massive team player who gave us his all, made huge contributions when we needed them, year-after-year for over a decade, helping us win shedloads of silverware in the process. Ole's 50 odd goals from 1998 - 2001 where we won three Premier League titles, the FA Cup and the Champion's League stack up pretty nicely against Van Persie's contribution over the 3 seasons he spent here. Watch back any season review of United in the late-90s or early-2000s and you'll easily see why Ole is well-loved. Van Persie rocking up to give us one year of his prime so he could win some silverware doesn't add up, regardless of how good he was in 2012-13.