No , the only thing that would affect broadband is if the extensions are wired in a non broadband friendly way ( and it’s been explained how to wire them in a sympathetic way ) or if you use an extension socket and the wiring used to the extension from the master is wired OK but the wiring itself is of poor quality….the test system has nothing to do with broadband performance , as it’s generally an in demand thing anyway…you report a problem, the line is tested , the test system isn’t continually testing and passing results to any broadband system…..ADSL/VDSL have dynamic line management,
