I believe that you can strike a balance. You dont have to be a prefect parent to have a well-adjusted, happy child. Attachment is a balance between security and support, confidence and freedom. Its all about allowing our babies to learn how to deal with their emotions (including anger, frustration, and excitement) constructively. This includes helping your baby learn to self-regulate behaviors, for example, sleep. Unfortunately, these are not things that that we can do for them, but we can teach them how to do it themselves in a safe, loving environment.
In fact, many families that I work with respond to a coaching analogy. You wouldnt expect a coach to get out on the field and play for his team, and likewise, as parents, we cannot expect our children to learn how to self-regulate without helping them learn the steps to do so. This does not mean that parents should sit and watch, rather, attached parents are involved and available, allowing their child to learn and grow and stepping in when they need assistance.
Just like a coach, you can give your child the tools, and help him learn to use them, but you cant do it for him. This especially applies to sleep. Children need to be taught to put themselves to sleep in order to have lifelong healthy sleep habits. Teaching oneself to fall asleep is a necessary life skill, and if your baby can only fall asleep with assistance (what I commonly call a sleep crutch), then they have learned that I cant fall asleep unless mommy rocks me or I cannot go back to sleep because mommy hasnt nursed me enough. This ends up causing exhaustion, frustration (for mom), and bad sleep habits (for baby).