Hello Kevin .
We were cluttering up Neils thread so I thought I would skip over here to try to answer your question about over looked issues with a gasifier system.
Good morning Kevin
I think not having the proper job or tasks for the gasified machine.
Don said it well when he mentioned he only drove 3 miles to work and it was not worth the effort to fire up for that short distance.
I have another example of my farm tractor and why I removed the gasifier from it. ( but still have it handy )
In the winter the tractors job or duty is to drive into a hay barn with tons of bone dry hay, spear a roll of hay and set out to the cattle . This takes from 10 to 30 minutes and the machine is not used again until the next day .
The amount of gasoline I would have saved is not worth the time or very small risk of fire .
In the summer the tractor job is working in the hay field with dry hay sometimes knee deep. Also when working in the hay always in a big hurry trying to take advantage of the suitable weather. Usually it will be my wife or son operating the tractor while I use another .( the operator knowledge is more important than the machine )
A job the gasified tractor is very good at is bushoging pasture land in the summer ( I have several videos of this , Wayne’s 444 International thread ) The problem with this is I also have a big bat wing bushog that covers 4X the ground and with the wings I am able to cut ditch banks and cut under low hanging limbs . I can save 3-4 days of work using the big rig .
One other example of gasification not fitting a task is my electric power needs . My electric power cost is less than $2 a day or average 8 cents per hour. In 30 years the power has been out about 5 -10 hours . No way I can justify gasifying my electric power to compete with the above.
With my farming duties I use a powerful and heavy work truck daily and usually not in any big hurry. The big problem with this vehicle is it only will travel about 6 miles on a gallon of gasoline . I consider this to be a very good application of gasification . 
All the above is based on availability of gasoline at a moderate price . If gasoline becomes scarce or if prices get too high the rules will change
Have Wood Will Travel