It seems that the original question is misguided in some sense. The Church does not DIScourage devotion to God, it ENcourages devotion to God. Losing track of this, somehow, leads to asking questions like this. The question seems to suggest that the Church is some dictatorial organization, where we’re walking as if on the edge of a razor and one false slip…and it’s all over – wrong.
It seems that the mind set that leads to asking this question should be readjusted in a charitable way.
Some of us can’t imagine why you would have this fear of Thursday versus Friday? God is not bound by time, for starters. Why would God not want you to meditate on the Gospel and live it?
This question seems to be based on a SERIOUS misconception, that you’re not worshiping God, but worshiping a rule, instead.