I get downvoted a lot, however, do we really need a tool to access another tool? I guess we don't - it is a pointless tool. If tcpdump is THAT important to you, it merits taking a deep look into the manual. Now, just because someone implemented a website with directions to a tool, it doesn't automatically translate to something useful.
To be fair mate: you are spot on. I'll never use it and I'll still be reading the man page and the HTML howtos for a few years to come. That said, someone had a bash and put a spotlight on something.
I have lost count of the times I have had to tell people to stop relying on "magic" and get a bloody packet capture out. Oh ... and log files.
I kind of agree with both sides of this argument but the one thing I often find lacking in man is context, which I know not really the point. But there is in the layout of the commands in this tool a better path to understanding the switches one might need to accomplish whatever task is at hand. Personally, I've spent far more time grep'ing my history than using man.
And true story, someone may have heard of at one point tcpdump or whatever but not know what man is. There's also people that transcend the platform multiverse that may spend hours, days or weeks building a bash script using linux tools that's used briefly or automated and will require familiarization if that process is ever reviewed/needed again. Tools like this and the regex visualization sites mentioned previously are great for that.