Creating a custom Profile provider

[fredd00]

Hi

how come the exemples for custom profile providers always iterate
through all the properties of a profile , isn't the profile supposed to
do 'on-demand lookup' unlike session variables that load all even if
you don't need them.

the implementations i'm looking at (
http://msdn2.microsoft.com/en-us/library/ta63b872.aspx ) , when i'm
stepping into will always retreive all profile info, which i don't want
..I only want to retreive the profile propertie that i need

is there such an implementation ?

thanks