TDM - good response!
I am confused still by the responses, being non-airport controller (but had a few months experience as you did), I cannot see how this instruction can be issued. As HD says, you don't cross a red stop bar, from what I can decipher, F isn't a red stop bar, but if you are to hold there, how much confusion (especially with non-based pilots) must there be with this instruction to hold there? Normal instructions to "hold at ##" means taxy but do not cross. Too ambiguous for me, can someone explain exactly why the instruction issued is correct?
Zon