"I don't understand this obsession with speed. ACCURACY is what is important."
Ye, accuracy is what is important. But think of the speed thing as exercise. Football players (in the old days I guess) would run around the field with tires roped to their waists---but not because they play a game that way! They become conditioned to run that much faster on game day.
When you are at home, without the distractions of a casino, and you don't have to look like you're not counting, you should be able to count much faster than when the money is on the line. That is (IMO) why one should care about speed. It is correlated with actual performance.
PS To answer the original question, I agree 35 is good enough for a beginner to go try things out in a casino (and realize how different it is than a kitchen table).