Interesting. Before we try to start counting chickens, is there any chance that you can replicate the experiment and provide some 'data' for us while
trying to limit variables?
Can you connect to LTE on each handset, one at a time (don't place phones near eachother), with all other radios off.
Then go to Settings -> About Phone -> Network Info -> Signal Strength
(this may be different or only in back end menus on the Sprint Galaxy Nexus 4G LTE)
And notate the approximate signal strength on each phone by itself from the same position. Lay the phone down so that you will hopefully interfere less with the signal transmission/reception. Also get readouts from different distances from the tower. More or less, a strong signal area and weak signal area.
I found this article particularly enlightening in regards to deciphering the "new" 4G approximate signal strength read outs in comparison to 'regular'/'old' (2G/3G) approximate signal strength read outs.
RSSI vs RSRP: A Brief LTE Signal Strength Primer - S4GRU
If you are adventurous, or want to go one step further, download and try Open Signal Maps for more options in data gathering. It can help you possibly locate the tower(s) and help determine the distance to the tower (though I'm not sure how/if Open Signal works for reading 4G).
Even doing everything I've mentioned we can still
not draw
any clear cut conclusions. And like RX mentioned, the network is not fully operational yet so this is all more or less silly.