Can demi glace be done with fewer steps
It depends entirely on how traditional you want to be. 

In England many, many restaurants put demi-glace on their menus which in reality has no resemblance to the traditional method. I've worked in these places, with 2-3 rosettes and one with a star. Yet even at that level we still use a "cow boy" method.

If you take the words literally.

Demi = half/inferior
Glace = shine 

Though my taking on this may be a little skewed I regard it as half a real jus. So instead of reducing your meat stock all the way down from 100 litres to 1 litre (little exaggerated I'll admit). So it's nice and thick and sticky. Take it half way so you end up with 50 litres. Then thicken it in order not to have brown water.

Traditionally roux is used, but in reality most kitchens these days will use gravy powder. Why? It's easier &amp; tastier. 

I watched a program by Heston a year or so ago where he was talking about roux when used in chicken pie or cheese sauce. He raised the fact that you make this wonderful tasty sauce then mask it with flour. As soon as you put flour in a sauce in binds to all the flavours and mutes them. Adding gravy powder (good stuff not bisto) with all its meaty flavours in just enriches your sauce rather than toning it down. So he used corn flour instead for his cheese sauce and ... I can't remember the chicken pie (cream I think)

So in answer to your question. Yes there is a way. Just make veal stock reduce it till it tastes good add tomato paste and thicken it  with a meat based powder. It'll taste as good as a traditional demi-glace if not better.

BUT

It's a cowboy way and it is far from the traditional method. 

You'll just have to weigh your time and resources against your need to do it right. Which is why professional kitchens often cheat.

Disclaimer: not all kitchens cheat but all but 1 of the 11 kitchens I've worked in, have.