The Cnet forums do not support such features at the present time due to a combination of the software used (Jive) and the limitations when it comes to resources, finances, and time involved. You may want to click here for a brief explanation our the head moderator, Lee Koo, concerning the forum software and its current limitations.
Personally I prefer Cnet's layout over all others for two reasons: First, it allows you to scan the subject lines and choose which posts you want to read, instead of scrolling through dozens of long replies to find what you're looking for. Second, it creates the possibility of having one thread split onto different topics/replies, whereas in forums such as Neowin that's almost impossible. (Difficult to follow individual subthreads, and demands the wasting of space to constantly quote someone else so that the reply is understood in the proper context.) However, I do hope that sometime in the future there will be an option for multiple layouts, so that all members can use the one they prefer.
John
Hello.
Is there a way to expand all replies at once so I won't have to click "next message" every time?
Thank you.

Chowhound
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