We estimate that the longest protein chain capable of exhaustive sampling of all its conformations within a millisecond is shorter than 15 residues. This reinforces the understanding of Levinthal paradox which emerged in the last decade, namely, that cooperative (all-or-none) character of folding and unfolding transition is indicative of the sequences selected such that reliable folding does not require exhaustive conformation sampling. The opinion is formulated that the discussions of Levinthal paradox should now fly to the new spheres.