Switcher question

[carnej1]

 The first NRE genset switcher which was built for UP was a center cab. It was built only about 2 years ago. It uses an MP15 frame with a center cab and 2 gensets in short hoods front and rear. However all the current units in their catalog have the cab at one end (with a low short hood in front) including units that are mechanically identical to that UP locomotive (1400 HP,2 engine). This is probably due to customer feedback requesting improved visibility..

[MILW205]

Also, part of the reason for an end-cab design is increased visibility during switching manuvers.  Granted, this means that you get a somewhat longer hood obstructing visibility when switching the opposite direction; but with the center-cab design, you have the hood obstruction no matter which way you are going. 

As another example, when PC/CR was re-engining Alco RS-3's with EMD engines from E's, the  units had at that point basically been relegated to local/switching duties.  If I am not mistaken, the first conversion example had the short hood removed entirely to increase visibility, resulting in a strange "porch" appearance.  (However, as far as I know, they made the judgment that the extra expense of removing the hood was not worth it, so that appearance was not repeated on subsequent RS-3 conversions.)   

[CSSHEGEWISCH]

Most center-cab switchers such as the 44-ton and various industrial switchers had two engines, so a center cab was not an unreasonable design.  A variation on the center cab was attempted with the C415, which had a V12 251 engine, but it had uneven axleloads and the wiring was unnecessarily complex.

[LM&I engineer]

center cab style switchers  had very small cabs. to put one on a switch engine today with the horse power that is required the cab would be even smaller.we are much better with end cabs and short hoods.

[CNW 6000]

With genset type switchers gaining popularity, would 'center cab' type switchers re-appear?  Why did they stop being made?