It's a design flaw if the associated computer is not on 24/7. And also in situations where the inside temperature is not reasonably constant (because the available offset is constant).
It's a design flaw that becomes blindingly obvious if the associated computer is not on 24/7. It remains a design flaw even if you are lucky enough to be using a setup where its results happen to be less serious.
Reportedly, the serial and IP loggers are better in this respect.
The serial logger is, indeed, supposed not to suffer from this problem - since it has to be powered from the console, which may be running on batteries, Davis may have been much more careful to minimize power wastage (as heat). The normal 'use case' for the IP logger would have it continuously powered, so a fixed offset would probably ameliorate most likely problems.
Which leads to the question - what's the similar temperature situation with the new WiFiLogger?
Worth asking, but here again, the normal 'use case' would have it continuously powered.