My first dog when I got out on my own was kinda like that... you'd take him out for a walk, he'd hit the first bush and cock his leg... he'd finish up, we'd come to the next bush, and he'd cock his leg...
And if you kept him out there for 20 minutes, and walked past 20 bushes in the process, he'd cock his leg 20 freakin' times...
Then of course, we'd go back in the house and he'd drink his water bowl dry...