With the exception of 10.10.6 above, use the strong groupsigns and the lower groupsigns in preference to the initial-letter contractions and the final-letter groupsigns provided their use does not waste space. [Space-saving takes precedence over this rule.]

Select the groupsign which more nearly approximates the usual pronunciation of the word and which does not distort the form of the word.

Do not use a groupsign if its use would seriously distort the pronunciation or hinder the recognition of the word.

Do not use a groupsign which would bridge the words which make up an unhyphenated compound word. 

Do not use the strong groupsigns for "ch", "gh", "sh", "th", or "wh" or the strong contraction for "the" when the "h" is aspirated.

Use the lower groupsign for "be", "con" or "dis" when the letters it represents form the first syllable of a word.

Do not use the lower groupsign for "ea" when the letters "ea" bridge a prefix and the remainder of the word.

With the exceptions of 10.11.3 and 10.11.4 above, in general use a groupsign which bridges a prefix and the remainder of a word unless its use would hinder the recognition or pronunciation of the word. In particular, use the groupsigns for "ed", "en", "er", "of" and "st".

Use a groupsign when the addition of a prefix or the formation of an unhyphenated compound word provides an opportunity to use a groupsign not used in the original word, even if this alters the usual braille form of the original word. However, do not use the groupsign if its use would hinder the recognition or pronunciation of the word.

Generally, use a groupsign which bridges a word and its suffix unless its use would hinder the recognition or pronunciation of the word.