I ran an awful lot of entries in my time and never tried to block. It would be quite hard to do. The stewards would take a pretty dim view if a horse was going out and in to constantly impede another horse . Because the jockey has to answer to the stewards , I would not have tried that. More so than the stewards, the jocks have to answer to one another. Those guys police themselves pretty well. Remember, if a jock pins you on the rail and his horse is dead , the rolls will be reversed at some point. Those guys will move out of the way for one another if the horse they are on is dead. Not always, but most times. Now, if they are both on live horses, and I do not mean favs. or longshots but horses that still have run left in them, then of course not. Both are trying to win but jamming up a guy with a dead horse will come back to bite you in the butt down the road. I would think that blocking is big in harness but really have no clue about it. I did witness at least one winner getting taken down once because the entry mate bothered several horses through the lane. The winner was well in front and the entry mate lugged in and bothered 2 or 3 horses making a run at the winner. The rules state that the stewards can do that if they deem it as interference by an entry mate. The winner bothered no one but was DQed and taken out of the money. Both halves of the entry earned no money. I am sure it happened more but that one comes to mind.
If any of you ever have a chance to watch a race from the far turn, you should do it. There is usually talking going on and you can hear it very well. With horses switching leads in and out of the turn, the horses are moving 3 feet in or out when that occurs. Plenty of jocks are screaming back and forth , especially if they are in trouble. Won't happen every race but if you watch ten races from the far turn, you will definitely hear what I am talking about.
As far as the back side is concerned , I am not sure what you mean. As a hot walker and groom , I lived on the back side for a couple of years at Laurel, Bowie, Pimlico, Del Park and Monmouth. At the time, I liked it. I never felt threatened in any way. I mean, there were certain people that you learned pretty quickly not to fool with but for the most part , the people were great. Obviously not a high rent place but some very decent people. Every track has it's share of nuts on it but there are many many good , honest people that live back there. A few years before I left , Mexican people started working at the track. I would think that there are many there nowadays. Some were jerks and would steal from you if they had the chance but again, many were nice guys or girls. Same as anywhere I guess.