I guess it would depend on the goal. If the goal of building an amplifier lies along the same lines as Peter Walker where "the perfect amplifier is a straight wire with gain" then I would think measurements would be more important since we can measure way beyond anything we can hear.
Do the best audio designers put their ears before the numbers.
Human hearing is what passions our love for music. Subjectively speaking, most of our hearing can’t be measured in a way that tells us how something will sound. So if we can’t measure our hearing to correlate with the numbers ( measurements) used by manufacturer’s of audio components, why are they so important? Assuming I’m right? Don’t the best designs always result from designers that approach their designs with their ears first and worry less about how it measures?