I know this is something that frustrates G1/G2 users, but I have never had an issue with it. I think because all my SLRs are older Nikons (8008s or FE2) with a single point of focus (in the center), I have no issue focusing on the critial point, holding the button, and then recomposing.
Confirming you did it right is another matter

(re: relying on the Contax focus scale for indication, rather than getting a visual image confirmation in the viewfinder)