Rossman is a snake oil salesman who uses substandard parts to repair Apple machines while bashing them left and right because he refuses to either go through the Apple certification process or use OEM parts. That is also exactly why the BMW analogy is accurate in this case. You could replace BMW with Chevy or Ford and my point still stands. Sorry, but Rossman is not as great a repair tech as you and your fellow Rossman apologists would claim. You also supported my own point when you said "after that they see a mechanic familiar with the brand" - because that wouldn't be "Joe's Repair Shack," if people are going for the cheapest possible repair, it would be someone with little to no training or familiarity with specific brands, just a general overview. Louis is also an outright a**hole, which goes a long way towards me not wanting to give him any business or views. Also, how would Louis know "how the circuit works from the schematic" when he doesn't have access to the schematics? You give him far too much credit for some things, then completely overlook other aspects of the situation as a whole.
Rossman has talent when it comes to electronics repair, there's no doubting that. However, his attitude towards Apple products (and his overall demeanor) and his use of off-brand replacement components raises a lot of questions from a warranty and workability perspective.
What snake oil is he selling? I’m not sure you know what that term means. What are the substandard parts he is using. How would him becoming an Apple Certified Macintosh Technician (ACMT) allow him access to an genuine capacitor, diode or transistor? It seems you’ve never actually been an ACMT at any time in your life. ?
Again, you struggle to grasp what an authorized service center can do. I worked for one for several years. I had access to GSX for the service manuals and training. I passed both the hardware test and software test (both $299) and took seperate “qualification” exams to be able to work on the then new retina machines and MBA at that time. Apple does not release board level schematics to their technicians. Apple will not sell me a capacitor or an IC for a logic board. They will not sell an authorized service center a backlight driver. I remember that the logic board for my 2010 MBP 13 C2D was $799?? No amount of Apple training material for their technicians teaches you how to read a schematic, how to use a DMM, how to solder board level components.
What do you mean by genuine parts in this case? There isn’t a genuine Apple
approved capacitor or Apple manufactured backlight driver, those are off the shelf components that you or I can buy from DigiKey, Mouser, etc. Some components are custom made for Apple and are proprietary so you have to salvage them from a donor machine since Apple will NOT SELL those components or any board level components for that matter.
As far as schematics go, you must be new at this, one can learn how to read a schematic and know how a circuit works based off the schematic. I’m not good with complex schematics/circuits so when I run into problems I post the schematic in question on a related technical forum and people much smarter than I are able to explain it to me. Thanks to various YouTube videos, reading, etc I can tell you how a basic speaker crossover works or how a power supply (dual rail or not) works. For the schematics I have for my audio gear, it tells you what the voltage should be at certain points (emmiter leg of a transistor, certain leg of a resistor, diode, etc) in relation to ground. The schematics that Jessa Jones, Rossman, and others have does the same thing. You have to figure out why a voltage is low or missing by
reading the schematic and checking components upstream
You must not have watched a Jessa Jones or Rossman video because they DO have schematics for those machines. Usually they leak from China (Foxconn)
The car analogy you made up was terrible, and like I said I’d bring what ever car to a person that specializes in those makes/models. Likewise I’d bring my 7 year old out of warranty MacBook Pro to someone that specializes in Apple products (Jessa Jones, Rossman, others)