Here is my two cents on this post...
Let me start off by saying I'm not a big DEI user. My info will be from a more general perspective that might help a bit.
First, the cars mentioned are from different generations. The 2015 Accord Sport is grouped with the Accords for
model years 2013 through 2015+ using a regular ignition key ( not push to start ). This is the latest / current gen. The
2012 Accord LX is from the previous gen ( 2009 - 2012 ) and a bit different. Making direct comparisons between the
two can be iffy.
As mentioned above, I'm not a DEI user. The current gen, regular key Accord's I have done are with bypass modules
from iDatalink, specifically the ADS AL-CA flashed with the DL HA6 firmware. All have worked flawlessly. The remote
started engine will not shutdown when a door is opened ( like PTS vehicles do ). Here is a link to a Pictorial on these cars :
https://www.the12volt.com/installbay/forum_posts.asp?tid=137247
At the end of the Pictorial is some info on the cars peculiarities. These cars come with a Factory Alarm system. Using
the iDatalink bypass module, it unlocks the drivers door prior to a remote start to turn off the alarm and you must program
the R/S or the bypass module to do a "lock after remote start" to secure the car. Using the iDatalink bypass module, the
R/S remotes have no issues controlling the vehicles' locks at any time. As noted in the Pictorial, the R/S FOB's can
only pop the trunk while the engine is off, just like the factory remotes. ( You can get around this by going directly
from the R/S to the car. ) Additionally, while the engine is off, the R/S FOB's give progressive unlock but when the
engine is running, the R/S FOB's unlock all doors at once.
While this might not answer your concerns directly, it might give you some insights on the operation and differences
between bypass modules, etc. Your info on "key-to-go" not being needed is interesting info. My understanding was
that all the bypass module companies required this ( Fortin = D-Cryptor, iDatalink = KLON ) for the transponder bypass
portion of the vehicle solution.
Soldering is fun!