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GitHub User: olistik
You have to understand the rationale behind each of these tools in order to understand if some of them can fit your needs.
Right now Compass gives you the ability to start from the ground up whereas Twitter Bootstrap is an excellent head start for rapid prototyping.
As Ryan pointed out, Bourbon provides a subset of Compass features.
Finally, Blueprint is a grid system that can be applied on top of Compass, but I suggest you to take a look at Susy instead if you need one.
As pointed out by Luca Guidi lighthouse ticket, it's a matter of ordering.
You should call
<% content_for :my_section do %>
<%# ... %>
<% end %>
<%= yield :my_section %>