Video display in Avidemux is stunning - why? - Can we replicate this?

[AvidMark]

Klite sent me to you.
http://codecs.forumotion.net/t1482-win-movie-maker-direct-editing-of-mov-files-in-xp#7534

It was like being hit by a lorry.
The 1080 MOV file captured via a logitech C920 came alive...... in an editing window!!!

As the above post points out.... even after saving the 80Mb MOV to a 4Gb AVI file; although very good in Win Media Player, it still didn't match the editing window of Avidemux!
Note: I did size the WMP window to match the Avidemux image size.

What is actually going on here (apart from obviously good engineers at Avidemux)?
Note: the klite pack was installed, so perhaps WMP simply wasn't using the best codecs?

Real World Scenario:

I'm in the process of producing a series of 'how to videos'  vis a vis a common engineering task.
I'm up to 44 vids - probably around 80 should cover the whole project.

Because the vids are (by good fortune) providing the right answers, I moved to thinking how the project might finance another, by offering interested parties a small 'club fee' to access the whole course...... say, ideally low cost around 'a tenner'.

Concurrent to these thoughts, I found avidemux - noted the high quality playback - and began to wonder if this could be replicated in a 'controlled access' scenario.

This is my first project involving video.
I do understand that orgs like youtube, 'auto deliver' the best format for the viewers device..... only that their rates generate very little revenue.

I guess this is a common question amongst video makers.
Is there a methodology or systems out there, that delivers avidemux quality playback, in a controlled access scenario?
OR
How are video makers solving this problem of 'delivering quality playback, whilst generating revenue to allow ongoing productivity'?

[AQUAR]

Short answer - map pixel to pixel.