The irrigate command is still referenced in Civ5, since the hotkey to construct a farm is I.
This happens every game for me as well. Can't play since micromanaging every worker every turn is horrible.
It appears destroyed hostile units (barbs/enemies) aren't properly removed from the square they're on (invisible data flag?). My workers always stop near plots where I destroyed hostile units. Every game the same thing. Expanding trough war is now no longer possible for me. I have to turn off barbs as well if I wish to play at all.
Even if I manually order them around. Anywhere near a plot where there used to be a hostile dead unit, they stop anything they do, as if they spotted them. Every turn I have to tell them again what to do. The only work around I've found now is to permanently keep a military unit on top of my workers in areas where enemy units died.
Edit: I'm running vanilla Civ5, don't have G&K or mods or DLC. I do however have minor changes to the base XML (simple data changes like increased culture from wonders)
So does this only happen to people who have automated their workers?
I mean, I have never seen this bug (with a little over 1000 hours played) and the only time I automate a worker is in the late game and even then I hardly do it.
Since the Firaxis don't fix this for you I mean perhaps it is time for us laymen to at least try to pinpoint the cause.
So this is a vanilla bug because of G&K then
I don't have G&K. I think the bug came after a vanilla patch.