I may be about to demonstrate an "ignorance" here but it has always been my understanding that "field strength" also has to be defined as being that field potential that exists within a defined set of dimensions in "space". It seems to me that for all practical purposes (as opposed to purely theoretical) that we are into an area which is usually defined as being " relative".

As practicing technicians/engineers/enthusiasts trying to achieve "results" I think it is more important that we have an understanding of the various parameters that both regulate and analyse our endeavours than to worry too much about definitions and pedantics.