We succeed with our typography when the viewer has 'got it'- really understood the message:
That means:
Maximum legibility for the viewing distance.
Amplification of meaning through character spacing, layout colouring of the words.
Emphasis on the important parts- the carry home lines.
Paraphrasing the message with break outs, subheads, quotes etc.
Ease of reading. A beginning, middle and end. Spaced chunks, pauses, rythym.
Graphic Design alone cannot create good typography. It's the sensitivity with which the message is delivered, amplified and paraphrased that creates to a large extent, the whole reading of the message.
Yes... the format, character and layout of words greatly influences our appreciation and understanding of their meaning. Perhaps too much.
Other typography rules of thumb
Upper & Lower case or sentence case is easier to read than all caps.
40 character rule refers to the maximum line length for ease of reading.