Lawyers and pro-say litigants ignore these rules at their own peril, as doing so is liable to get your case dismissed outright and at the very least will seriously annoy the Judge.
This is not quite true. The general rule of courts is to expect attorneys to follow the court's rules regarding legal pleadings. An in pro se or in pro per (that's someone filing a pleading on his own behalf without an attorney) is generally given more latitude because he or she is not an attorney in the interest of justice. The court's expectation there is that the document be readable, it make rational and logical legal arguments, and that they be properly cited. In California and in federal courts, successful habeas corpus petitions written on toilet paper have been filed by prisoners.