I recently received a motion from opposing counsel that relied on (and even block-quoted) an appellate procedural rule that was superseded nearly 10 years ago. The motion sought leave to supplement the appellate record, which is not required under the "new" rules. Instead, any party is authorized to direct the clerk or court reporter to prepare, certify, and file in the appellate court a supplemental record, which automatically become part of the appellate record. See Tex. R. App. P. 34.5(b), 34.6(b).
Every justice, staff attorney, or law clerk at the court of appeals will recognize this error and will know that the lawyer either (1) has not handled an appeal within the last 10 years, or (2) didn’t bother to check the rules before filing this motion (or both). You can avoid wasting the Court’s time and protect your credibility as an appellate advocate by reviewing the rules applicable to any motion you intend to file.