I was also a bit curious about Sain's rating, so I quickly sped through LHM to look at enemy stats in the chapter I got Sain to lvl 8 in. I ended up at the beginning of 5. I favoured Sain quite a lot - Lyn was only at lvl 5 and Florina only at lvl 3, but in the end, I got Sain to a point in which he could double, admittedly borderline. In the chapter I came across only 1 brigand (not including the boss) that hit 6 spd.
Since Kent reaches 7 str at say lvl 3, he'll have around 1-1.5 chapters where Sain is beating him in offense (2HKO vs 3HKO) whilst Kent gets around 2 chapters where he beats Sain in offense.
This means that up to chapter 6, Kent is beating Sain by basically no margin. However, afterwards Sain begins to be able to 1RKO (or simply beat in offense) things that Kent cant, like Knights and some Bosses. Suddenly, the two cavaliers are now equal, maybe with Sain being a little better.
With this in mind, how the hell is Kent half a point in front of Sain? It should be the opposite, maybe equal if you really like Kent that much.