lancer, well, what if you cant see them? ie. If you are waiting long and they are short?
Suffice to say that it looks like this is an ATC function, as a driver, you can verify (to some extent) and observe (again, to some extent), but in reality, isnt your focus on other things at this point in time?
Other questions, not directed at you, guidance shows that one should rotate before the leading ac has rotated. As far as rotating before the other ac rotated, does one rotate at a visual point, or at V1/Vr?
Hypothetically, if one sees the leading ac rotation point, and one passes that point before V1 is reached, what does one do? (ie. you knowingly set up a wake turbulence encounter?)
I see the guidance on this from the FAA and such, but in reality, it is not reality.