I used to work for Prozone, a very big statistical analysis company based in Leeds, with, at the time (I'm going back to 2003) half of the Premiership and a few bigger Championship clubs as clients (as well as some in Holland, France UAE and international rugby teams). Now this was analysis on a much grander scale, at the time it involved installing expensive camera and computer equipment at the grounds that cost upwards of 250,000). The company has since been bought by the global STATS company. It definitely works and even more so when you are one of (or maybe the only one) at your level to be using it. It definitely gives an advantage. Obviously this advantage diminishes as many other clubs at your level start using the same system (shouldn't be an issue at the level we will be at)
Interesting stuff, but the difficulty would be in obtaining reliable and substantial stats on your opponents at Evostik League Level, as surely you need the fullest picture possible (taking your point, for the sake of this argument, that it does work - it would be interesting to see, well, the statistics of results for clubs who employ this method against those who don't).
Incidentally, if we appointed managers on the basis of their statistical record, it wouldn't exactly look good for the current incumbents.
By the way, the 250,000 figure (all figures are as of 2003) was just to install the equipment at the ground. Each match analysed was charged at a rate of 5000-10000 depending on the level of analysis required. For the full package, every player was tracked in 1/10 of a second intervals for the whole game as well as match analysis on all events (tackles, fouls, throw-ins, etc, etc. etc). A full analysis DVD was then produced and brought back to the team in question within 36 hours of final whistle. The package was delivered to the clubs by Eufa qualified coaches (employed by Prozone). So you also build up useful data on your own team that you can't possibly see all players for the full 90 minutes.
Yes, you are correct to a certain extent, that you need to build up a database of information before it starts to become of use and our level next season, I'm assuming we'll be at ground zero, so to speak.
As regards effectiveness, a good example would be a team called Al Ain from UAE who we took on board and they were the only team in their league to employ us. The league was dreadful at the time, it was like watching primary school football with everyone following the ball. After coming on board they had the most successful spell in their history, winning the league 5 out of 7 seasons (runners up in the other 2, this was between 1997 and 2004 (I moved to Ireland after than and left the company, so don't really know after that).