Glyn, how/where a limb flexes, depends on how it is tapered. And "taper" should be understood as the product of the degrees of thinning AND/OR narrowing of the limb along its length.
In order to achieve even flexing... Recurves, since they're generally wider than longbows, will lose more material in width and less in thickness. Longbows are the opposite... losing more in thickness and less in width.
Similarly, in the wood bow realm... a true pyramid bow is tapered entirely in its width... while its thickness is consistant from dips to tips. Conversely, a narrow English longbow does the majority of its tapering in thickness... losing very little in width compared to the pyramid design... but both have lost sufficient material due to tapering to achieve even flexing of their limbs.
As far as the number of lams, most laminated wood/glass recurves have 2 of wood and 2 of glass... most... not all. Sometimes one of them is tapered, sometimes both of them. That's up to the bowyer. I make mine with one parallel and one tapered.
There is always the possibility of limb twist. But it is due a lot more to misaglignment, or material consistancy and quality that it is limb width.
The main advantages of a laminated recurve over a recurve induced by heat are... they are comprised of several thin layers of material which are easier to bend into sharper more radical curves without breaking, which can enhance performance... and the many glue joints maintain rigid shape with use.
That said, personally I prefer narrow limbed, all wooden recurves... sometimes heated and bent, sometimes sinewed, and sometimes laminated(all wood). My wooden recurves are typically no wider than my longbows. From the front view, you couldn't tell them apart from a longbow.