If lrctool is run on the empeg, I think we'd have to manually adjust this offset in the *1 FID, or risk garbage data being fed into the MP3 decoder.

Yes. The MP3 decoder is quite good at skipping garbage, but it's still not an ideal situation.

As with any other metadata editing, the Right Way to do it is to get the ID3v2 tags right before the *0 file goes on the player in the first place -- or, if the file is already on the player, to fix the PC side copy and use Replace Tune.

Peter