Doc, I am a reovering environmental planner/biologist and I once did a stint at the Volusia County MPO ( daytona beach area for the folks not from Florida). I see your points quite clearly and the way highways are funded it occurs on a 7 year cycle for projects in the transportation improvement plan (TIP).
The problem is as the costs of fuel increases it takes more money out of the pocket of the poor and middle class. Thus money for travel or running a boat or what ever is shifted to what is needed and the other stuff is cut out. Thus demand for fuel drops because travel takes a hit, fishing takes a hit, camping takes a hit and so on and so on. When gas was $1.80 or so I would trailer my boat to my brothers place in Titusvile and I would fish 3 or 4 times in the spring. Now I fish once in the spring and it is largely due to fuel costs to fish and the fuel costs to drive around my home town to get to work and so forth because my budget does not allow for so many trips. Also when folks travel less here, my income drops too which compounds the effect of me being able to travel to other places. Then think about 30 to 50 million people all making similar choices in the travel behavior because of their financial situation changes. Think about the economic impact of marinas, bait stores, tackle supply places, and on and on when gas is cheaper. The more money those guys make, the more they higher, the more taxes their businesess pay and the more money they have for their own lives The impact of cheaper energy here is significant.
The gas tax is based on consumption and when consumption drops due to high prices, keeping the gas prices does not make since. I say help the economy recover and you will see improved revenue from increases in demand for fuel. Adding more coss to the middle and lower income folks will only keep our economy stagnant. Guys like you and I Doc have to make choices. Guys like Frank here who just bought a brand new Freedom 307 I suspect dont have to make similar choices when it comes to travel and purchasing things. So higher fuel costs impact us all, but as one makes less and less the costs of fuel hits the budget more and more.
Want more revenue, then stimulate demand for a consumption based tax and you do it by making the product affordable and cheap, not by making it more expensive. Art Laffer has that cool little curve about taxes and revenue. There is a sweet spot for taxes and gas taxes that sweet spot is clearly not $3.50 a gallon as evidence by total highway miles traveled is down over the past 5 or 6 years as a direct result of the price of fuel.
If we need more revenue for roads the solution to me is get the economy back on track, get demand for labor up, then salaries will naturally rise in a competittive job market. The more money people make, the more they spend which means more tax revenue for the government overall with greater economic activity. Adding more taxes to fuel simply because we are use to paying $3.50 a gallon is nonsense. The coawards in the Washington DC ( both parties) did not have the courage to raise the gas tax when it was $3.80 a gallon and the roads needed it then ( as in a few months ago), now are floating this idea out there because they think Americans can just pay it. Well, we can pay it, but raods and bridges are not an economic development plan for the nation. Organgic job creation based on genuine demand for products and services is the solution and affordable energy makes it all possible.