New Spawn Influence Zone for CTF and Assault?

Hello All,
Can anyone explain (in detail please) the new spawn influence zones that are on most of the maps and are set up for CTF and Assault? From forge I can tell which team they will affect, but what does -15.94 have to do with anything when the range is only -15.88 to -16? From what I can see it means that the more teammates you have on a certain portion of the map, the more likely your team is to spawn away from you. I tried testing this the other day with some friends and even when we weren’t in the zone we were still unable to spawn our teammates anywhere but our base. I have been unable to find an explanation anywhere online including Waypoint. Before the last update I understood the spawn system pretty well and now it seems like no matter where my team is I will spawn in the base, even if they are not under fire. Any help would be appreciated. Thanks.