Using GMT instead in SL, to make it easier to relate to (for those living outside the US) and daylight saving time at different times in different countries makes it even more confusing.
We use English so that everyone can understand it, and using GMT (without daylight saving time) is also something everyone can relate to when it comes to time.
Alternatively, some function where you can translate SL time to our own time zones or at least to/from GMT.