Would Gohan's Ultimate Form have decreased the time of a Fused Warrior?

[Steven Bloodriver]

If Son Goku and Ultimate Gohan had used the Fusion Dance or the Potara Earrings, would their fusion have been given a shorter time to exist from the usage of Gohan's Ultimate Gohan given to him by the Elder Kai?

[theherodjl]

If Son Goku and Ultimate Gohan had used the Fusion Dance or the Potara Earrings, would their fusion have been given a shorter time to exist from the usage of Gohan's Ultimate Gohan given to him by the Elder Kai?

I doubt it, the Ultimate state eliminates the stresses of SSJ and its upgraded forms making it even more conservational than FPSSJ. Its just a glorified base form with the power of SSJ3 taken even further, it shouldn't reduce fusion by any noticeable amount. The reason Vegetto Blue & SSJ4 Gogeta had their fusion time cut in half was due to their bodies having to upkeep the strongest forms of SSJ there is but in double the amount.
Obviously fusion never accounted for transformations such as SSJ due to it being exclusive to Saiyans. I don't know about the Metamor variant but the potara has existed as long as Rou Kaioshin has which is somewhere over 75 million years, the Saiyans were probably barely evolved marsupial-simians when fusion was invented.

[dragon boss z]

It's hard to say. I initially thought no, but SSB at least in the anime doesn't seem to have bad energy drain and they defused extremely quickly. However this could be because int he manga version SSB has high energy drain. I'll just go with maybe a little.

[Lionel]

The ultimate state is supposed to be the cumulative release of a fighter's potential combined with an enormous amplification of the power so that it exceeds their natural limits. Far as we've seen, it doesn't appear to be a cost-intensive transformation that one has to strain in order to hold. Ultimate is more of an organic compartmentalisation of all their power into what we call "base".