To take it a step further; if the participation rate is less than a number that shows unity, say 90% or more, revealing it could be seen as showing weakness. But that weakness could be buttressed by revealing what will very likely be a survey showing pilots demand a contract that reflects the value they feel they are providing to company's mission. To reveal the former in such a scenario and not the latter would be very disappointing, and hopefully prod survey participants to question why those in a position would make such a decision.