That has to be lore. Klein is not all that consistent on colors. Usually lineman are blue, dykes are red, long nose are yellow, but you can make an all yellow set if you try. And they have other handles (insulated, VDE, journeyman, heavy duty, glow, double dipped special editions
)
According to Klein, the 2000 series are heavy duty cutting (nails, screws etc.) and the other ones are not for anything beyond ACSR.
That being said, I have seen many tests and myself have used regular Klein’s to cut stuff I should not and they have held up ok. I have a set of HD213-9NE did fencing work with and cut split pins etc.
So reading a Klein part number is actually pretty easy if you know that 2000 point.
D213-9NE is a Dipped handle, 213 is the model, 9 inch, New England style lineman.
The highest optioned is something like the
J2000-9NECRTP
J is journeyman handles. 2000 series and then you get stuff at the end if it has a crimper (CR), fish tape puller (TP), or you can also get a thread cleaner instead (TH).
You can also get glow in the dark hi-viz (GLW suffix).
If you want the heavy duty cutting, they sell the lineman and some dykes with some strippers for $70.