You must have ridden the 566, not the 586. The 566 has a taller head tube and tube shapes designed for more compliance.

http://www.lookcycle.com/products/

The head tube is 20mm taller and the reach is just slightly shorter.

It's not hard to compare the geometry of the two frames, if you post the size that you own and the one you test rode. The problem is you probably have no idea what stem angle and spacer combination was used on the bikes you test rode. That makes a big difference.

I'd caution against comparing changes to fit with those from a more compliant frame. All it takes to raise the bars about 20mm is 11-12 degrees more stem rise. Even with the same stem length, the reach is also reduced. If you flip an 84 degree stem to 96 degrees it raises the bars about 20mm and withthe same stem length, shortens the reach by about 7mm.