Sensory method means listening to the noise. Traditionally this was done by an experienced mechanic simply listening to the noise and using their own judgment as to whether its too noisy overall, or might have a particular worrying sound such as tapping or knocking.
Its possible they now use a sophisticated sound meter to measure the sound on a scale with a pass/fail result but I suspect its still more likely to be human judgment .
I'm not a professional but I would have thought a high precision Honda engine probably alters valve clearances by using a variety of shims with a precise thickness rather than relatively crude threaded adjusters. (I may be wrong) If so its unlikely to need its clearances altered during the normal service life of the engine. They might get noisier on a very high mileage engine but by the time this becomes excessive enough to need fairly complex adjustment the engine may also benefit from a more major rebuild in other areas. If the cylinder head, valves, valve seats,cam shafts etc are replaced or recut then valve adjustment may be required, but as part of this major rebuild/refurbishment.