Here's what I do:
1.  If it's just Jas drinking & a horse comes in, I ask, "would you like me to 
wait?"
2.  I don't wait,if a bunch of horses are coming, or a group that's riding 
together, they can wait for each other if they want.
3.  If I want someone to wait for us - I ask.
4.  Otherwise - I let riders know that they needn't wait.
Gotta say it though - on our last ride, it was hot, humid, & Jas was getting 
her first real drink about 15 mi. out.  A group of 3 came into the river.  One 
riders horse began bumping us, & "jockying" for space, (mind you Jas was head 
down, drinking) upstream of us.  Then, promptly shit about 3" from Jas's nose. 
 The rider said,  "sorry, he always does that". 
That   r e a l  l  y   got me!
Connie H.