As she says: "Do not leave off the final sounds"
Remember, 3 different cases to consider when pronouncing regular pasts:
1) Pataca, chouzas, xefe (unvoiced/voiceless sounds). "t" (an unvoiced consonant) is an exception when it comes to these voiceless consonants affecting the pronunciation of the past tense of regular verbs.
2) Voiced sounds, vowels and all other consonants. "d" (a voiced consonant) is an exception for the pronunciation of past tenses.
3) verbs ending in "t" or "d".
It is all very clearly explained on this video and on the one I posted on this same matter earlier on this month (October 2009).