"I would venture a guess, GRJ, that Lionel has developed an on-line detailed parts listing out of necessity - to counter balance the difficult situation people & service techs encounter from Lionel's dismal quality control issues while on the other hand, MTH, has no urgent need for such a detailed consumer repair parts listing due to far fewer cq issues."
I would venture a guess that you haven't been in the hobby very long. No offense, but this is almost totally without factual basis. Been reading another forum and its disgruntled curmudgeons perhaps?
Facts: Lionel has had its parts inventory on line for many years. MTH's problems with parts availability has been off and on for years. MTH has had a dealer inventory on line for years, Lionel never has. Matters to some and not others.
The notion that MTH has had no quality issues, and Lionel's products are universally defective is promulgated by a few deeply dissatisfied and prolific individuals, not representative of most people's experience. Passing this continual and disproportionate dissatisfaction of a few off as reality serves the hobby poorly when such comments discourage hobbyists for no sound reasons.
Lemons happen to everyone, including MTH. It's how the company deals with the problems that inevitably occur that make the customer experience good or bad. If Lionel has had more than a few problems it's because they are essentially the only company doing new tooling and innovating, with such things as state-side production, LC/LC+, steam locomotive features, etc. Bound to be some teething problems. Every company, from Atlas to 3rd Rail to K-Line to MTH, as well as Lionel has had their screwups. MTH, to their credit, has stuck with what they do well, and continued to do it for some years with no changes to speak of other than the WIU. That's what happens when the market is overall shrinking for everything but starter sets.