Many years ago I used to poll the lcd for status - the problem is when the lcd dies to code sits in a dead loop unless you add a timeout for this. Doing this adds a lot of complexity to the lcd code - so most people just use delays as for the most part you're just locating the cursor and writing to the data memory. If the lcd decides to fail, your code continues as if nothing was wrong! Also you save an i/o bit in that you can tie r/w to write only. That's my excuse!