One of the thing(s) that I find interesting RE: mechanical diagnosis is that proper diagnosis require all human senses to tell what's wrong with it: sense of smell (burning, oil/ATF smell, burning antifreeze, oily smoke, etc.), sense of vision (what can be picked up visually?), sense of touch (feel the vibration), sense of hearing (what's the noise?), etc.
I know no 2 mech are of the same level of sensitivity when it comes to detecting differences between something wrong or something not-wrong but here are my 2c's RE: sensing what's wrong with bearings: you need a strong sense of feel(body sensation), and a keen sense of hearing and patience in order to narrow down pesky integrated wheel bearing problems these days, or things that doesn't make sense. While I must say that I'm an idiot when it comes to sensing A/T shrudders, I can tell what's wrong/fault in suspension RE: wheel bearing with fairly good accuracy, all thanks to my acute hearing (yes, I'm also an ultra-fi/audiophile during afterhours, specialising in tube audio gears and SETs) and also strong sensation on my back (that one is from rallye + SCCA slalom racing in my early years).
One of the things that I cannot stressed enough RE: in the field of auto mechanics is that (a) learn to protect yourself properly from chemical harm, toxins accumulations and burns. nitrile gloves, ear muffs and protective eye gears are a must (b) learn to pamper your body for maximum/peak sensitivity: that is something that I've learned through years of minor abuse but one thing I really enjoy the most is the relative quiet/serenity in my suburb neighbourhood where I can sleep through the nite with avg noise. Also: I'm against noisy exhaust, stoopid boombox (never done that in my life), MP3 music through closed-circuit headphones, etc.
That's what separates me and the Honda dealership monkeys when it comes to diagnosing wheel bearing problems such as the one on my dad's 6th gen civic....
My 2c's worth.