I would have thought that Ctrl + F was sufficiently well - known for including it to be unnecessary.

Apparently not to some, my OP quote was from a beta topic. 

Plus even for folks who do know about it, they still don't always make the connection because of the lack (so far) of the regular search box on that landing page and so they try Ctrl+F on that landing page and it doesn't work so it confuses them a bit.

All we're doing is giving them a hint.

Cheers,
Christos