canon - What is the effect of the number of cross-type focus points on sharp focus?

Canon claims that EOS 6D has special capability to focus in low light, but it has only one cross-type sensor and overall only 11 focus points. Does only one cross-type focus point in the Canon EOS 6D affect its ability to focus in low light? Is it correct to assume that more cross-type focus points produce more accurate and sharper focus?