Most powerful component of secure attachment for a child

U of Minn Center for Early Education and Development, Early Report, Attachment and Bonding issue:

Studies about parent-infant relationships show that the most powerful component of a secure attachment is early, sensitive care for children, characterized by:
* recognition that even the youngest infant can signal her needs and wishes;
* accurate reading and interpretation of infant cues and signals;
* letting the child's signals, rather than the parents' needs or wishes, set the agenda;
* and consistency or predictability over time.
Of course no parent can or should jump at every little signal the baby gives; but the child's overall experience should be that her signals are effective in getting a response--that caregivers are available and willing to respond. In order to respond sensitively, a parent must understand the cues and signals of the child, be willing to respond, and have the emotional strength and social support necessary to sustain sensitivity over time.

This would make the whole "cry it out" method questionable in its long term benefits, it seems.