Well, that's great but what if the experts have different opinions and ways of doing things?
Case in point:
Agent Noah Lukeman, who is a big name in the industry, wrote a free e-book entitled, How to Write a Great Query Letter: Inside Tips & Techniques for Success. In the book he states that in the initial query, it is unnecessary to include the actual names of your main character(s).
Now hop over to a blog post by Elena Roth, an agent for the Caren Johnson Literary Agency, entitled Anatomy of a Query Letter. Here, you can clearly see that the sample query provides names.
There are also more differences in the way each agent approaches a query and how they think a query should be written.
This is not uncommon. Writers, editors, and agents (lions, tigers, and bears!) each have different ways of doing things and it doesn't necessarily make the advice bad, just different. So how do you know how to navigate them? With a little bit of heart, you should absorb all the information you can, look for the common ground and construct your query based on how you feel it should best be handled. Then offer it up to other writers in a closed, password protected forum or group and get feedback for it. Rewrite as necessary based on their reactions and send it to the agents/editors you've researched for your work.
By the way for those links above; I recommend reading both as they each have great insight.