Re: Why? Good question.
I think your stats are backwards...
I see the article on paddocktalk states the opposite but comparing Speed & Liuzzi's starting grid positions as listed on
www.formula1.com will show Liuzzi had a higher starting grid position on 6 of 10 matchups: Malaysia, Bahrain, Spain, Monaco, Canada and the US.
Of the races in which he finished ahead of Liuzzi only in two, Malaysia and the US, did both Toro Rossos actually complete the race.
The stats that the Speed channel put up are essentially nonsense, academic stats. Laps ahead, top ten laps, yadda yadda. The fact is Liuzzi was a better qualifier in 2007 and they were tied for championship points with zero and neither was consitently finishing or qualifying ahead of the other.
Speed is obviously a better driver but if you're him you've got to get those results and not let Liuzzi ever beat you, especially in qualifying if you want people to believe you're better. Suggesting that Speed is a substantially better driver when Liuzzi outqualifies him is a tough sell because it's difficult to prove mathematically with bottom-line results stats. He is definitely better than Liuzzi but didn't show it every time out and especially where it counts--qualifying and race positions.
I think he was probably good enough to get some points and finish a little better than where he did but his constant failure to consistently beat Liuzzi and the fact that Webber and DC are blowing him away in the other Red Bull didn't bode well for him. He certainly was in no position to whine.
Speed got absolutely snakebitten several times this year as his best starts ended in retirements. However he was absolutely not in the top 10 of drivers and maybe not the top 15. If he was European his skill level alone would not have carried him to F1. He was in F1 because he was American.
I guess he thought that if he called out his team he would be able to preemptively assign the perceived blame to them instead of himself and possibly have another team take a chance on him believing, perhaps, that it was the team's fault that he hasn't been successful. Unfortunately, however, his vociferousness just made him appear to be an ungrateful, undisciplined, undiplomatic big-mouth. No doubt he did not get a fair shake and was run out of town but his results were just short of putting himself in a sympathetic position for another team to commit to him.
We're going to see Vettel do much better I think in the Toro Rosso once he gets a handle on how inferior the chassis is to the BMW. If Vettel does not do well I think Speed might have a chance to sneak back in through some team's back door, maybe Spyker or whatever they become. It does seem the veterans are able to handle the inferior cars better than the newcomers as their fundamentals are stronger. I do think Vettel, unlike Speed, is a real talent and he'll be blowing Liuzzi away and hanging with DC very soon.
Speed I think is finished in F1. He's better than he got credit for but not good enough for me to want to hire him as opposed to putting my energy towards looking for fresh young talent.
After all 19th or 20th isn't DFL. 
