whether i can solder directly...

Hi friends,
I am tuning filter.My workmate told me that can not solder the components when tuning,and have to disconnect demo board.I do not know why i can not solder directly(My VNA is 8753ES and the iron has ESD protection),and I feel it is so inconvenient.Have all of you it the same as above when tuning?
Anyone can give me a good idea how to make it convenient when tuning if not?
Thanks,

Most of the RF engineers probably disconnect the board from the test bench when tune or doing matching of the circuits.
I never did this, always I worked with the board connected to the VNA, Spectrum Analyzer, Signal Generator, or whatever, having just the DC supply disconnected.
But definitely needs a good ESD soldering iron.