To be honest, most of the questions that were answered in past sessions of letter from the producer broadcast were from the Japanese forum (to be fair, many of the questions asked by English users were also brought up by the Japanese users), just as how most dev responses on this forum typically consists of a Japanese response to a recent thread in the Japanese forum first, and then an English mod searching for a (usually) dead English thread on the same topic created long ago and then resurrecting it by posting the translated response there.

Having said that, the lag issue was brought up in the Japanese forum before, but no official response was provided there either (the lag issue seems to be far less prominent in Japan, which might have affected the response priority, as the discussion never really took off).　

Anyway, I have added a really succinct question about network lag in the Japanese Ask the Producer X thread. Feel free to Like it if you think it'll help...
http://forum.square-enix.com/ffxiv/t...=1#post1564839