That's understood SP, however it appears clear that there is no definitive answer here. Even the 747 isn't much help.
I think what is clear though, is that just because something may be legal and written in black and white, it may not be the most sensible thing to do.
Round here there are 40 mph speed limits on straight dual carriageways, you can then simply turn off it onto a single carriageway country lane and you can legally do 60mph. Just because you can, doesn't mean you should!
Besides, if post number 2 was a simple 'No!', discussion wouldn't take place and we wouldn't be learning anything.