There will always be studies that show both sides of any issue. You really have to try these things out on yourself and see how you feel.

I personally don't believe it has ay real effect on metabolism. But I do know that to grow and to the energy to train hard enough you need to eat a lot more food than you imagine and by eating smaller, more frequently, it will probably help digestion.

That's how I do it. Eating massive meals just slows me right down for hours.