Inboard Engine Taxi on Four Engine Airplanes??

[No Fly Zone]

Gents (and ladies), please help me understand…
Over the years I’ve often observed four-engine turboprops taxiing to and fro with only their inboard engines turning. Jets do so as well, but it is more difficult to observe which engines are powered and which are not. I recognize that that two engines will provide adequate power for taxiing, and that this is generally a fuel conservation choice. What I do not understand is why ground operations typically use the inboard engines, usually numbered two and three, with one and four shut down. It seem to me that using number one and four would give the pilot slightly better control of the airplane through the use of differential thrust, when necessary, perhaps including some reduced wear on tires and brakes. While not all four engine aircraft taxi on two, all the time, I see it often enough to note that the two turning are nearly always the inboard engines. Can someone please explain why 2 and 3 are usually chosen, as opposed to 1 and 4? So far, the only viable reason that I can come up with suggests that I may have something to do with either hydraulic systems (brakes & steering) or electrical generators. If it helps, I’ve seen this most often with Electras and C-130 Hercs. Thank you in advance. There must be a reason...