Oil bulls, curb your enthusiasm.

The sharp recovery in benchmark oil prices from their lows earlier this year started around the time that Saudi Arabia, Russia and others first mooted the idea of a freeze to oil output. Yet ahead of another meeting of the world’s biggest exporters this weekend, there are still reasons to think that oil has had the best of its current run.

Sure, an output freeze, if agreed, would cement the idea for many investors that the worst of the oil crash is over. Trouble is, a freeze would have little real impact on the oil market this year.

The International Energy Agency this week noted that producers are pumping at near record rates. And the exporter with the most potential growth, Iran, looks least likely to play ball.

But in holding out simply the hope of coordinated action among producing nations, even talk of a freeze has helped lift oil from its doldrums, deterring bearish bets. Indeed, notes Ole Hansen at Saxo Bank, investors have ramped up bullish bets on prices, with long positions in Brent crude reaching record levels earlier this month.

Improved sentiment is supportive. But fundamentals, while better, still look flimsy. Unexpected disruptions to supply, in Nigeria, Iraq and elsewhere, have removed 800,000 barrels a day from the market, according to Barclays. Such cuts are likely to be temporary.

Developments in the U.S. are also helping the market. Onshore oil production is falling. And investors may also be reassessing their view of how quickly shale producers can respond to a rise in oil prices, argues Chris Kettenmann, chief energy strategist at Macro Risk Advisors.

The assumption had been that nimble operators could quickly capitalize on rising prices, capping any rally. But increased attention to fragile balance sheets and banks’ exposure to the industry, as well as the availability of manpower and equipment after a long period of retrenchment, raises doubts about the speed of the bounceback.

Still, this again may not be enough to sustain a rally. Despite the cutbacks, the jury is out on the critical question of how U.S. production might respond. Mr. Kettenmann, for one, expects a forceful response from producers as prices rise, albeit with a one-to-two quarter lag. Given how recent the shale boom has been, there is no road map for how producers are likely to behave.

There is also a technical factor to consider. Short-term supply disruptions and unexpectedly strong demand figures have helped fuel a rally in near-month prices relative to longer-dated futures contracts, particularly in Brent. That though squeezes the incentive to store oil, and could mean investment stockpiles are released, again boosting supply.

Ultimately, the tone from this weekend’s meeting in Doha could be as important as tangible action. Still, the oil market looks positioned for near-term disappointment, rather than delight.