Hi guys, long time reader, first time poster...
I think gauging someone's skill is entirely possible from their stats, but a lot of it depends on youre definition of skill, and it would be infinitely easier if EA did more elaborate stat tracking.
I would define skill as someone who is capable of turning the tide in battle. Meaning, can you:
Defend flags against multiple enemies... i.e. can you more often than not kill the three assault people attacking your flag if you're the lone spec ops left and low on ammo? stat: defended CP
Take out vehicles as infantry, either assualt with the n00b tube and favs, anti tanks and anything, and spec ops and anything. I REALLY wish EA tracked how many vehicle kills you get as infantry... stat: AT/AA kills, explosives
Capture Flags, either by yourself, or in a group of people: I would define an expert player as one who could, more often than not, assault a flag defended by two or more individuals by his or herself, and effectively defend their respawns, stats: captures/hr, cap assists/hr defended cp/hr
Deal with snipers, noob tubers, c4 whores, tank whores, attack choppers, bombers: not so much an issue now... but I never got what all the hype was about C4 whores and n00b tubers, I so rarely died from them simply because I knew how they worked, and thus knew how to avoid them. Avoiding the attack chopper is another important skill... see that tank coming down the road, let's run at it and shoot it with my M-16 to piss it off... sniper in the distance, then let's sit out in the open and pop a few shots... just a general knowledge of tactics that OTHER players use to defeat you goes a long way. stats: none that really reflect this
jet whores: normally, I don't think that simply jet whoring, i.e. bombing infantry can completely affect the tide of a battle, however, I think that it can effectively shut down good players and make their lives more difficult... THEREFORE, I would say that the mark of a good jet pilot is not how many kills they get with the jet, but how many airplanes/choppers/bombers they've shot down, and how many apcs/vodnicks/humvees/FAVs/boats/tanks they've destroyed. Again, these are stats I WISH EA tracked. This stat system has such an opportunity to be a data miners dream... stats: driver kill assists maybe, for bomber gunners... time in airplane, K:D with plane
chopper whores: a good chopper pilot will NOT have a large K:D with his chopper, why? Because a good chopper pilot sets up and lets his gunner take ALL the kills, concentrating on not crashing, avoiding rockets, AA, .50 cal, and setting up for the next kill. A good gunner with a bad pilot is worthless, and a good pilot with a bad gunner is just as bad. I am of the opinion that the attack chopper can make or break a battle, especially if the commander is worth his salt and lets the chopper pilot know which flags are being assaulted. stats: chopper k:d, driver kill assists, kill assists, chopper time relative to kills for pilots
medic whores: I've never understood why people hate the medic so much, calling the guy who revives his teammate 100 times a round a whore... plain and simple, if you got revived, you didn't lose a ticket, and you're team has a better chance of winning. If I'm in a cross fire, and the medic revives me and I die, and I get revived, and I die, and I get revived, and I die, well... it's my own damn fault for not moving my ass when I get revived. I would rather be revived and die a hundred times, than die once. Now... this needs a caveat, a medic is an assaulting machine as well, and no well defended flag assault will work without medic support. Medics NEED to be aware that they have powerful weapons, grenades, etc. stats: revives, heals, and most importantly, medic K:D ratio (which incidentally, is something I'm proud of)
snipers: spot out infantry, tanks... EA doesn't track this, but I personally feel you should receive an assist point, and it should be tracked seperately of kill assists, for spotting a vehicle or infantry that get's destroyed whilst it was spotted by you. Captures as a sniper I believe are good indicators, a sniper will take the long route and capture a back flag, giving his or her team a new spawn point from which to attack. I don't think K:D is a good indication of a good sniper... stats: captured cp/hr, claymore kills, sniper rifle accuracy for bolt action rifles (again, not specificically tracked)
commanders: a good commander will solely make or break a team... I am a ardent believer in this, yes, the team has to follow directions, but more often than not, anyone who bothered to join a squad, will enjoy regular updates from the commander, I certainly do. I don't think points as commander reflects this, but I do think the W:L AS commander does reflect command skill.
Put this all together, and you get the SPM... which I think along with infantry weapons K:D is the biggest reflection of skill. If you have a high SPM, you're doing SOMETHING right... I would define good as 2.0 ish, excellent as 2.4 or more... and game breaking as anything higher than 2.7... Some of the guys on the top ten have them in the 3.8 range... that's insane. Again, whoring with armor will give you a high SPM, BUT... if you are whoring with armor, you're winning for your team. Infantry K:D is good simply because it states that when you went up against equal opposition, you won X percentage of the time. If you're K:D with assault rifles is 2:1, then excluding deaths by vehicles (which artificially lowers your K:D since you can't kill a tank with a carbine, or an assault rifle) you won 2 out of every 3 battles with infantry, or... 2/3 of the time. In all liklihood, excluding deaths by vehicles, if your k:d is 2:1, you more likely won 3/4 battles for a pure 3:1 K:D versus infantry...
I don't think accuracy has any bearing on how good someone is... I think they TEND to be correlated... but I wouldn't consider it absolute. If you get a gold star, kill 50 people a round, capture 10 flags a game, but have 5% accuracy... then god speed... if you've got > 25% accuracy, but can't cap, kill, or do team actions... well I don't want you OR your uber accuracy on my team.
Stats that I think will expose a poor player masquerading as a good one:
time as medic, but low heals/revives
time as support, but low support action
time as engineer, but low repairs, etc... (like me :( )
armor kills >> 50% of total kills
helicopter and airplane time but low kills, or, if low kills, then low driver ability points and kill assists also low (indicates bad pilot)
punishes (I wish it tracked how many times you punished... that would expose the n00bs right away)
lone wolf time: nuff said, join a squad, do something
good K:D, heals, revives, accuracy, but low SPM: sure you revive teamates, kill guys, but you only do it for 10% of the game and sit around in the back and jack off the rest of the time... I honestly don't know how bf2 is exciting for some people with Low SPM... I would be bored silly...
karkand time: now, I need to put a caveat on this... there are people who only play city maps, and then there are people who ONLY play karkand. Enjoying city maps is a playing style... enjoying karkand only, means you spend your time perfecting one skill, but would probably be useless at first in any other map... I fervently believe that a good player in karkand has the capability of owning another map, but they will need to practice. Besides, I've never understood why whores pick karkand to whore in... sharqi is a MUCH better map on which to whore...
Anyways... my $0.02... flame away...