I will use a restroom unless I just absolutely cannot hold it in any longer(as in, I've been holding it for a few holes already and things aren't moving fast enough). It seems like some guys just can't help but go take a piss whenever they see a tree.
a couple weeks ago my friend and I were the second group off...a single was in front of us. We tee off on the 4th hole(from the tee you are blind from about 170 in to the hole...well as we come up over the crest..there stands the single right by the green taking a leak. On top of that, he's facing towards us as we come up the fairway and he stood there for another minute before he thought it might be better to turn around.
A few years ago I was playing solo and had played through 16 holes....and on the 15th and 16th I could feel a little bit of poo radar starting to ping. Anyway, I think "I'm just a couple holes from being done, I can play through it" so I go ahead and tee up on the 17th. I swing and I think I damn near poo'd myself..it was the worst feeling in the world. I had to get to a bathroom and quick! It felt like I hit every bump on the course as I rode to pick up my ball and then speed to the clubhouse. I barely made it in time to not make mud in my pants.....thank GOD!