Fat Burner / Sugar Burner & Metabolic Typing?

Hi

There's allot of diet books and articles out there telling people to reduce the amount of Sugar in their diet, indicating that 'a person should become a fat burner as opposed to a Sugar burner'. Logically speaking they are encouraged to coax the body towards burning fat reserves for energy instead of relying on sugar.

My question is this. If someone does eat allot of sugar, does this mean that their body will slow down in it's ability to burn fat (and that's not just when you're eating Sugar but long after that sugar has been digested and your insulin levels have dropped to a normal levels) or is there some kind if switch in your body that turns over after a few weeks and makes your body burn more fat for energy after you give up sugar?

I don't want to get into a discussion about insulin resistance and I understand the relationship between Insulin and its suppressing effect on glucagon and therefore fat burning. But after the effect of the sugar has gone and your insulin levels have returned back to a normal level (and not suppressing glucagon) then is there a lag in the negative effect of those high insulin levels. Could in fact be the cause of what is often referred to as the cause of this situation of there being fat burners and sugar burners?

It's whether there is a real lag effect long after an elevated level of insulin that I'm interested in. If there is anything out there I can read on this (books or articles) which explains this I would love to read it.

Thanks so much.