(xml) Builder question

I love it!

I'm not sure why builder switches the position of its content argument
depeding on block vs. immediate:

    builder.tag("content", "attr1"=>"val1", "attr2"=>"val2")
vs.
    builder.tag("attr1"=>"val1", "attr2"=>"val2") { content }

Why not consistently use 1st position for node attribute, 2nd position for
nested node content? I hope it is not just to get the Ruby convenience of
not needing {} around trailing hash argument.

Thanks!