The canons are one thing, but St Nicodemus' commentaries on them don't hold the same authority. He claims a lot of things that are not the norm in any Orthodox church I've been to, whether Greek or Russian, True or World, e.g. he says you should not eat fish on Palm Sunday, and that you should keep the Wednesday and Friday fasts during the week after the Publican and the Pharisee.
But my real point is not that the Triimeron total fast is not authoritative; on the contrary, every source I've read confirms that the authentic practice is to observe a total fast from Clean Monday to Clean Wednesday and the Presanctified Liturgy. Rather, I'm saying that you should not attempt to observe the full strictness of the fast without some guidance. Really, this is orthopraxis 101. I suggest reading Fr Steven Allen's advice on how to develop a rule of prayer for related advice.
I think we're meaning different things by "spiritual father". I don't mean the old-style Elder who you could submit to totally as if you were a monastic; I simply mean the priest or bishop you confess to regularly, who knows your weaknesses and can give you appropriate rules. As Vladimir Moss notes in his article against false eldership, a characteristic of modern false elders, like Elder Ephraim, is in fact excessive strictness in the kind of rules they impose on the laymen who confess to them, as well as excessive demands of obedience, so that their spiritual children cannot make any decisions for themselves without consulting their "geronda".
Again, I strongly counsel readers against trying to go it alone when it comes to choosing a rule of prayer or fasting.