It's an interesting experience, testifying before a parliamentary committee. To anyone thinking of testifying, by all means do so. But first, carefully read the terms of reference, and address each in turn. Carefully read the guidelines. Do not use emotive language, just be factual. If called upon to testify, wear a nice suit, be highly respectful of the committee, don't get off the point, and keep the message simple and relevant. Prepare, prepare, and prepare; have facts to hand. If relevant, include factual comparisons with other counties. Cite your sources. Carefully check your submission for grammar, spelling, typos, presentation. Write a short summary of your points, and bring it with you. Give copies to the committee members. Thank them for the opportunity to testify.
I don't think an anonymous submission has as much impact as one that is signed.
Remember: you want to be taken seriously. The committee wants to hear from responsible citizens.