Ok, at the risk of making a fool of myself I'll have a go at your "quiz"
First off He's not using any stands and the jack is fully extended which makes for maximum instability!
Regarding that bottom pin. In this example it looks to be in good condition but they are well known to corrode in position including the wee clip. The hammer he's using is just ridiculous! if you get "violent" with it it breaks off the wee lug it fits into on the caliper carrier. Gently gently is the way to approach this pin!
I like to take the top pin out, check the rubber boot and give it a wee clean up and relube with ceramic or silicon grease - not a mineral based product, like copper grease, which will degrade the rubber and sometimes cause the slider to jam up by swelling rubber bushings on some deigns - however if you're not going to do that, checking it's free is a good idea but he is being a bit rough on it? might damage the boot? Watch too that you're not stressing the hose.
By gum, you just couldn't have got anymore life out of those pads though could you?
Now comes the really big no no. He blows the dust out with an air gun! Unbelievable in this day and age! Even though asbestos has been outlawed in friction materials for years now you absolutely do not want to risk getting this stuff in your lungs. Liquid brake cleaner is available in aerosol cans everywhere now a days, just use it (it comes in handy for degreasing other stuff too).
Then he has to, quite rightly, retract the piston to make room for the new, thicker, pads. Here we might have a bit of disagreement about how to do it. By the way I'd have been having a very close look at the dust gator on the piston before going any further. The problem centres around protecting the ABS unit from ingress of "foreign bodies" The general advice is to clamp off the brake hose and slacken the bleed nipple so that as you push the piston back no fluid can travel back towards the ABS unit which might jam up the internal valving, instead it is ejected through the bleed nipple which can be messy! - Don't forget to retighten the nipple and top up the reservoir when you've finished. In practice there are things to consider, not least of which being that if it's an old car the bleed nipple may well be hopelessly corroded in place and will snap off if you try to undo it! The "foreign bodies" to which I refer above will pretty much be rubber debris. Either small bits of rubber from the internal hose liner or rubber dust from the piston seals. Perhaps also, on a very old vehicle, some small rust dust particularly if the brake fluid hasn't been changed regularly. So, my thinking on the subject is that if the vehicle is quite new, maybe having it's first pad change, there is very little risk in pressing the piston back and allowing the fluid to return to the reservoir (watch it doesn't over flow - someone may have topped it up as the pads wore down) If the car is older than that I'd try to undo the bleed nipple but if it's seized I'd probably just press the piston back anyway. I've done it many many times this way and never, so far, had a problem (shouldn't have said that should I)
Applying grease to the back of the pads and caliper carrier? well yes, good idea. But, now a days, copper grease is not recommended for a number of reasons, although it is still widely used without any particular problems I've personally observed. You can buy specific ceramic based greases for this purpose, all factors, Halfords, etc stock it and I now use it. If you are going to apply any grease - and it MUST be a high melting point producT - then use it sparingly. The idea is to get it between mating surfaces caliper/piston to pad. Most of the grease he applied is doing nothing. Of course you absolutely do not want it anywhere near the friction face so, I say again, be sparing in it's use. I would have cleaned up the curved locating area in the caliper carrier where the rounded ends of the pads rest and given them a light coating of lube too. Don't forget to lube the wee pin too and squeeze some lube into the wee hole the clip fits in so it has a chance of coming out next time, Of course I noticed he does that.
Well, what have I missed out on? I rather like his gloves though, must get a pair!
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