Just as channeling may result unintentionally from formalities di- rected toward other ends, so these other ends tend to be satisfied by any device which accomplishes a channeling of expression. There is an evi- dentiary value in the clarity and definiteness of contour which such a device accomplishes. Anything which effects a neat division between the legal and the non-legal, or between different kinds of legal transac- tions, will tend also to make apparent to the party the consequences of his action and will suggest deliberation where deliberation is needed. Indeed, we may go further and say that some minimum satisfaction of the desideratum of channeling is necessary before measures designed to prevent inconsiderateness can be effective. This may be illustrated in the holographic will. The necessity of reducing the testator's intention to his own handwriting would seem superficially to offer, not only evi- dentiary safeguards, but excellent protection against inconsiderateness as well. Where the holographic will fails, however, is as a device for separating the legal wheat from the legally irrelevant chaff. The courts are frequently faced with the difficulty of determining whether a partic- ular document-it may be an informal family letter which happens to be entirely in the handwriting of the sender-reveals the requisite "testamentary intention." This difficulty can only be eliminated by a formality which performs adequately the channeling function, by