This takes me back to my CAA ATCA interview at Manchester Airport back in 1981. One of the board members, who was an engineer, asked me if I thought a helicopter flying an ILS would disrupt the localiser with its rotor blades! I bumbled something like it would have to be very close to the localiser aerial for this to happen. He then gave me and the other two board members a lecture on how he thought it would!! I got the ATCA post and went on to do my ATCO cadetship and now all these years later have never heard another thing about this!!
In ATC we give larger spacing during LVO's because of the possibility of disruption of localiser/glidepath but I do remember once being told by a very senior BA captain that these distances could be greatly reduced and best leave it to aircrafts sensors to decide on go-around rather than sending aircraft round due to less than required spacing!