Without wishing to sound condescending, you are missing the point somewhat.
This isn't actually about the stats per se, it's about assessing potential players as realistically as possible. In CM, the best way of doing this is via the stats.
In reality players are assessed by clubs on a number of occassions, and may even train with potential purchasers before any decision to purchase is made (look at the players that went from Peterborough to Spurs as an example). Clubs will scout players a number of times (to check consistency amongst other things), and each time they will gain a more rounded picture of a player. The game (not CM3

) does this by slowly revealing the stats.
No matter how much you trust your scout, if you are looking for a winger and he rates a player as an excellent propspect but he only has crossing of 1, you aint going to sign him.
I stand by my earlier comments, that it is probably unrealistic to sign a player after scouting them once. In CM3 you gain nothing from scouting a player more than once. CM4 has made this more realistic and is a good thing. Whilst some things are subjective I don't see how this one could be argued (but would be quite pleased if it were - debate is healthy

). It's no more likely that a LL manager would spend his entire £20k transfer budget on somebody they've had scouted once than Alex Ferguson spending £3 million on someone he knows next to nothing about.
*whilst writing this I've realised that Sam Allardyce signed a couple of players after only watching them on a video, but this is extreme, risky, and I'm amazed that Bolton's board sanctioned it*