yep. i have a 5-year-old siamese who eats the same way. sometimes he even closes his eyes like it makes him eat faster or something. he's almost exactly the same size as yours, but he would be twice that size if i let him. he reminds me of someone eating with their hands, and stuffing the food in and licking their fingers LOL.
for some reason i've seen a lot of siamese act like this. or maybe i just noticed because that's the kind i've been around most. it's kind of weird though.
My little Flame Point Meezer kitten is a total piggy when it comes to feeding time. He will make a big mess with his food and gets it all over the place, and then head for his sister's bowl and root her right out of it. Oink! Oink! Oink! He also seems to have a hard time cleaning his plate for some reason? He ends up getting Pate' style Friskies and Fancy Feast all over his head LOL
I think that's true up to a point, both of my cats are total "foodies", especially the new kitty. He does not know his limits and he'll eat until he gets diarrhea.
I've always heard as well that you should start watching a kittens weight if they get too fat after 6 mo's. I could be wrong. My kitten is right at 6 mo's.