The bugs are what make Farmville challenging. Without all those "Your game is out of sync with the server" messages, lost gifts and lost neighbors, it just wouldn't be the same would it?
But the annoyances are just annoying. The Farmville Cooperative Farming feature has bugs aplenty, but it also has designed-in annoyances. When you are done seeding and everyone is just waiting for the crops to come up, you can't join another project. You don't really know how long it is going to be before you can join a project either, so you have a wasted period of up to a day.
That's a minor problem. But what happens if someone forgets to harvest their crop or can't do it. There are, let's face it, higher priorities in life than playing Farmville and it is just barely imaginable, isn't it, that someone will be called away on urgent business, or get sick or meet the love of their life and forget about Farmville. The crops they seeded are never harvested. There is no way for anyone to make up the loss, and the project goes under.
C'est la vie.