How to merge arcs in a geometric network

[MikeCasey]

I have arcs that are connected with network junctions and would like to merge them into one arc.  When I try the standard edit/merge tool the tool is grayed out.  I can do this just fine with arcs that do not participate in the network so must be something with network rules I'm thinking.

I'm also wondering if less network junctions and more vertices would affect performance such as draw times.

The arcs I'm looking to merge are continuous series of arcs with no branches or junctions.

[MikeCasey]

I tried the merge tool in a geometric network while in ArcMap 10.2.1 and it works.  It does leave the network junctions behind and the junctions still behave as normal. When I move one the line moves with it.  If I disconnect it and move it, the junction moves and the line stays put but a new junction appears.  I can delete the junction and that works with no new junction taking its place.

Does anyone know if being able to use the merge tool in a geometric network is a new feature and if so should it be leaving the network junctions behind? 

I have many transmission lines that have many arcs per line and would like to merge them into one arc per transmission line.  I intend to do so but I’m not sure if I should be deleting the junctions that are left behind.