With an emergency, the objective is not to fly the quickest pattern possible, it's to be back safely on the ground as soon as possible, with the greatest probability of success. If you save 10 seconds by doing something that substantially increases the risk of wrecking the aircraft because you flew it into something, that's probably a poor tradeoff.
In the pure "minimum time possible" scenario, you want to minimize distance flown & maximize speed (up until the point you're slowing down to land), which means things like steep angles of bank, minimum time spent climbing, rolling out of your final turn right over the numbers, and so forth. So you fly the pattern at full throttle at a really low altitude, with a continuous turn to final at a high angle of bank, chopping power and descending so that you simultaneously roll out of the turn and reach your target landing airspeed all right over the numbers at minimal altitude, with no left/right offset. Cool airshow trick if it works, but an awful lot of opportunities for things to get off the desired parameters, at which point your choice is to go around & try again (false economy in time "saved" with the aggressive pattern there) or else to try to salvage a bad setup, which - especially with the added stress of the initial emergency - is a recipe for destroying the airplane yourself and achieving the worst possible outcome from the emergency situation... which might well have been survivable with a more controlled, less aggressive flightpath.
Unless it's something you're highly proficient in, (i.e. you regularly practice exactly this for your airshow routine), the absolute minimum-time pattern described above is not what reasonable pilots would choose, even with a cabin filling with smoke and screaming. They probably wouldn't fly a leisurely, wide pattern like initial training, but avoiding things like stalling, flying into the ground in a moment of distraction, or being so high on final you land long & overrun the pavement are all higher priorities than saving those last few seconds.
If the situation really is so dire that you absolutely must land right now, then (in a light aircraft, at least) perhaps it's time to consider landing straight ahead on a road or a field or a body of water, rather than returning to the departure runway. Scenarios requiring that much urgency, though, are more the stuff of imagination than of common occurrence.
