Maybe I'm getting old and grumpy as not only do I not understand them but they really do irritate me far more than is reasonable.
Why do people put random. ........ In texts and emails? I read them as passive aggressive pauses, even when the message is clearly friendly!
"Great....Thanks for doing that....I really appreciate your help......" is it just me that reads that as a pa message? (It absolutely wasn't)
Or
"Hi. ...what time is the meeting at? ......I can't find my notes. ....."
"I'm back in the office on Friday. ....are you available to discuss X please. It shouldn't take long. ...I just need help understanding Y"
All received from people whose work involves writing to a very high standard. One is a notorious pedant. So is it just me who doesn't get the ........s? Am I just a silly old grump who needs to embrace the dotty dots? 
