The problem is that there is massive selection bias. If you're one of the very top researchers in your field you are much more likely to A) produce world class research and B) never have much problems with funding.
Conversely many of those funding their own research are doing so because they cannot get any other funding, which may be an indicator that they aren't very good.
Really? I seriously question that "because". If I had FU money I would definitely start my own lab and pay for research out of pocket. Science is fantastically fun if you don't have to care about funding (and by extension tenure) and only publish because it's nice to get feedback from your peers (rather than because you need X papers to get your next grant and keep your job).
Conversely, writing grants is a total bore.
A "because" I would be more willing to buy: if you made that kind of money for yourself, odds are you spent your prime years achieving that and therefore haven't dedicated the time to science that's necessary to be at the top of your field.
> Conversely many of those funding their own research are doing so because they cannot get any other funding, which may be an indicator that they aren't very good.
... at selling. In my experience the skill sets needed for aquiring funds and those for doing research don't have much in common.
Conversely many of those funding their own research are doing so because they cannot get any other funding, which may be an indicator that they aren't very good.