It may be that he did not wish to commit himself in any way to the contents of a treaty until the Covenant of the League of Nations had been accepted.

It may be that he preferred not to let the American Commissioners know his views, as they would then be in a position to take an active part in the informal discussions which he apparently wished to handle alone.

None of these explanations is at all satisfactory, and yet any one of them may be the true one.
Whatever was the chief reason for the President's failure to furnish a working plan to the American Commissioners, he knowingly adopted the policy and clung to it with the tenacity of purpose which has been one of the qualities of mind that account for his great successes and for his great failures.

I use the adverb "knowingly" because it had been made clear to him that, in the judgment of others, the Commissioners ought to have the guidance furnished by a draft-treaty or by a definite statement of policies no matter how tentative or subject to change the draft or statement might be.
On the day that the President left Paris to return to the United States (February 14, 1919) I asked him if he had any instructions for the Commissioners during his absence concerning the settlements which should be included in the preliminary treaty of peace, as it was understood that the Council of Ten would continue its sessions for the consideration of the subjects requiring investigation and decision.

The President replied that he had no instructions, that the decisions could wait until he returned, though the hearings could proceed and reports could be made during his absence.