Secret menus on modern sets

My 80's vintage Zenith color sets had secret menus that allowed the repairman to fool with or check various settings, am wondering if my present Sony Wega set has this as well. Anyone know?

I bought this set as a demo and never got the owner's manual and Sony's website is useless in this regard......does anyone know what the "VM" control is or does? This is listed within the "Video" menu. There are 3 choices, Off, Low and High. I don't see any difference at all between any of them!

One neat thing is that there's a tilt correction which allows you to tilt the picture left or right. When at the showroom I noticed a few Sonys askew and asked the "salesman" (IE: ignoramus) about this.....I feared that perhaps there was a bad batch of sets. Turns out they were just adjusted goofy, probably some trouble maker like me who knew about this and screwed with them! LOL

Anthony