I improved the large sign back to more quality than it could have had when created, text did not come back (hoped it might). Took a spare pointing sign of quality 50, wrote 50 characters on it (maximum) and burned down quality in forge to 36. Text was still on it, but fire damage lowers quality without the sign getting damage to repair so on i went to bashing it. Smashing and repairing, the sign still had its text of 50 characters. Maybe large signs are special, or planting a sign makes them behave differently... testing testing... planted the pointing sign behind house, damaged it a bit more, rotated to see if text updates when moving planted sign, text did not change. Repairing the planted sign also did not remove the 50 characters. Finally, using rename to edit the sign, as expected any editing of text removed the no longer allowed characters. Test sign now has 36 characters instead of 50. Either large signs behave a special way or i forgot to test something. Now back to regular wurming.