Interesting to read obstruction problems .
Here in NZ we have had the new obstruction since 2002 .
We have been very hard on it ie if a player is standing in the running line of a runner and in our judgement impedes that runner then it is obstruction .
At my most recent tournament I had a delayed dead ball once in 6 games in top level mens fastpitch .
This indicates to me players are learning quickly to get out of the way .
Also the obstruction rule was brought in to stop a lot of the unnecessary contact between fielder and runner and therefore get rid of a lot of niggles/aggression etc .
Police it hard now and find it easier later on .