AUGUSTA — A hastily scheduled meeting of the Legislative Council last week, with Appropriations Committee members invited to sit in for a command performance by Gov. John R. McKernan’s budget chief, lived up to its advance billing.

There had been no advance billing. And there was little to report afterward.

Even so, for close observers of the continuing debate over the state of the state’s finances, the gathering proved instructive. It demonstrated that Democratic critics of the McKernan administration have so many quarrels with the Republican governor’s handling of the budget that they don’t know where to begin stamping their feet. And it showed that the McKernan administration and its GOP allies are dug in defensively as deep as ever, and most desirous of declaring the debate over and done with.

Still bothering many Democrats are the continuing fiscal 1990 closeout maneuverings by Finance Commissioner H. Sawin Millett, whose explanations of abnormal bill payments and bookings during May, June and July are still subject to Democratic challenge.

Others by turn insist that fiscal 1991 maneuverings, since the new year began on July 1, are more troubling but similarly designed to cloak cash-flow shortages and revenue shortfalls until after the November elections.

About all the two sides did agree on — and this acknowledgment by Millett would have qualified as news were it not such a nod to the obvious — was that the next two-year state budget, effective July 1 1991, will presumably need at least $300 million from sources not yet in evidence.

As each state budget becomes in practical terms the base from which the next is built, continuing obligations gather a momentum of their own. And the architects of last year’s much disparaged package to avert a $210 million biennial budget gap — Democrats and Republicans alike — concede that they all but emptied the cupboard of one-time only revenue-raising gimmicks.

Millett sought to soothe the skeptics by noting that revenue increases from budget cycle to budget cycle have run routinely above $300 million. But that drew complaints from doubting Democrats who said the administration’s most recently revised revenue projections, from January, were too rosy to begin with and look even worse in light of more recent economic sluggishness.

On that point, Millett appeared willing to meet the critics halfway.

“If we were doing those estimates today, I think we would reshape them,” he allowed.

If all this from Wednesday’s gathering sounded much like the dialogue in Maine’s gubernatorial campaign, it was. The Democratic challenge to McKernan, now championed by former Gov. Joseph E. Brennan, began in Augusta long before Brennan decided to seek another term in the Blaine House.

So the latest confrontation between the two sides in the budget debate drew low marks for originality. But as a sociological sounding of the current state of relations between the combatants, it was eminently enlightening.

Senate President Charles P. Pray could tell Millett with a straight face that he had been invited to address “allegations, accusations, whatever you want to say” about the administration’s budget balancing so that Millett might “quell some of those.”

Millett, equal to the invitation if plainly doubtful that Pray hoped he would “quell” anything, told the president that he was “glad to have this opportunity.”