Like you said the "knocks" against him in the off/preseason were - age, new system, weapons, and he's not that good to begin with.
I think the only valid issues, which you could be rightfully concerned about, were system.
He's older, sure, but hes not that old. You may not like him or think he was very good. I'm not claiming that he is an elite like Brees or Manning but McNabb (when healthy which should be the other biggest concern) has produced well in his career. Especially on a ppg basis, not a stay healthy and win total season points basis. Many of those years when he was putting up good numbers gets us to issue 3, weapons. Sans the TO year and the recent emergence of Desean his weapons were Westbrook and garbage. I almost feel like Moss, Galloway, Cooley can be considered an upgrade to some of the WR Philly trotted out for McNabb in the past. At the very least it is a push.
If he could put up productive numbers with Westy plus garbage I think he can do ok with what he has now. The first 2 games aren't really a good example of what he can do. I think there are too many factors to get a good idea of what we are dealing with yet, but I think there is more good that we have seen than bad considering new system, ankle injury, etc.. I wouldn't get too hyped up on the Texan game though because I think their pass D is rotten.
I just went back and looked at his stats a little bit. I'm not a McNabb or Eagles historian so I’m guessing a little bit here. It looks like he officially took over as the starter in 2000, maybe lat 99, but I’m just gonna pull his stats from 2000 onward. His totals over 10 years then look like 31,925 passing yards and 208 touchdowns through 136 games. I don’t want to skew stats too greatly but it looked like he missed at least a game or more in 6 seasons we means he probably went out early with an injury in 6 of those 136 games played. If we knock that down to 133 (to be accurate on time played) it looks like he averages 240 yards per game and 1.6 TDs per game throughout his career. He also averaged about 22 yards rushing and .2 rushing TDs a game.
So his average game breakdown would be about 240 Passing – 22 rushing – and 1.8 TDs (rushing/passing combined). We score high for QB’s in my league (6 point passing TD) so I combined them. In my league that averages out to about 22.4 points per game. Not too bad.
I’m happy that some people slept on McNabb in my league to hit on more en vogue up and comers like Kolb, Henne, Stafford, Flacco, Eli, etc… as their QB1. It left McNabb for me as a very solid backup to Schaub for little cost, and maybe even trade bait later in the year.
It seems like if he can get the new system and offense down (looks like he’s on his way) and can stay healthy (that’s more troubling) I think he can start putting up those career average ppg numbers this year once he gets a bit more comfortable in a few games from now.