My only concern with any "parent" alignment rules are the knock-on effects.

1. For long method calls/chains, the whole block of parameters are indented a long way, encroaching on the 120 line limit.
    ```erb
    <% a_really_long_block_variable_name.method_call_with_a_long_name :foo
                                                                      must_set_this_parameter_to_be_awesome: true %>
    ```

1. When the method name changes, it would mean changing all the spacing on the params