I really couldn't disagree more. Paint is almost never squeezed directly from the tube onto a brush, or dabbed from a tube.
I discussed this with my mother who has been doing calligraphy for 30 years. She used to make banners for all sorts of occasions using acrylic tube paint and has never used the paint in that manner. She doesn't remember anyone in her group that has used this method, either. Over the years this entails at least 20 people as the group has grown and changed.
From two art instruction sites that I could find online for free,
both include a palette or other (saucer) for an initial deposit of the paint.
http://www.art-is-fun.com/artists-supplies.html
http://www.wikihow.com/Paint
More than likely the description of block letters has to do with with a printing style (as opposed to cursive) that is, by default, wider because of the width of the brush. The style of printing will still carry the characteristics of the writer. Only stencils would deliver such a uniform look as to be devoid of the writer's innate style.
I can always identify my mom's style whether block, cursive or special font.
This is why it would have been important to publish the photo of the message on the door in order to see if anyone could recognize the style. Also it should have been examined thoroughly by a handwriting expert.