All proposals should, at a minimum, conform to the specified length and other requirements indicated in the call for papers. Additionally, they should express a clear argument; they should not be simply summaries of events or statements of fact. Papers which only report on the activities of a given project, without drawing any conclusions or exploring the significance of those activities, will be at a disadvantage in the review process.
It is extremely important to include adequate references, both to establish the argumentative field within which your paper is participating, and to substantiate and document any claims you may be making. If you used no other sources in preparing your proposal, it is probably too vague to be successful; if you used other sources but did not document them, your proposal may be less than intellectually honest.
The role of the reviewer is to assist the Program Committee in assessing the quality of the proposals submitted. It is not primarily to decide which proposals should be accepted or rejected, but rather to provide information which the Program Committee may use in making its decision. A secondary role for the reviewers is to provide feedback to the authors.
A good review will provide constructive feedback to the proposal's author, suggesting ways in which the paper may be strengthened. This feedback is important whether you are recommending that the paper be rejected or accepted; if the former, it will enable the author to submit a stronger proposal next year (and may encourage a new member or a young scholar); if the latter, it may result in a stronger paper being presented. In either case, it projects collegiality and an interest in others' work.
Whatever you may think privately of the proposal or its author, and whatever you may know (or think you know) about the author, it is absolutely essential to be uncompromisingly professional and courteous in reviewing all papers. Rudeness of any sort is destructive to the morale of the community and is absolutely unacceptable in a review. Any comments which are purely negative or ad hominem should be addressed solely to the program committee.
To a certain extent, given the small size of the humanities computing community, the identity of paper authors has often been evident to the astute reviewer, and discretion has always been required in handling that knowledge appropriately. Since COHCO is discontinuing the anonymization of papers during the review process, this discretion will be even more necessary. The identity of the author will necessarily be a factor in evaluating the proposal, but it may operate in complex ways. A famous name should not be taken as de facto evidence of a strong proposal, and a weak proposal by such an author should be given the same critique as a weak proposal by an unknown author. However, there may also be cases where an author's known expertise may strengthen the value of the proposal: for instance, a representative of a standards workgroup might have more credibility in discussing the standard than someone with no involvement in the effort. Reviewers should feel free to be candid in their comments to the Program Committee in cases where they feel the identity of the author plays a significant role in the assessment of the paper.