At the risk of contradicting what is in the owners manual, I also think that 3 - 4 mm is a bit loose. Here is my two cents worth (sorry, no nickel here).
The key at the lever is to have at least a little play. No play can mean that your clutch slips and / or wears out. The other key, as mentioned, is to have the lever at the gearbox at close to 90 degrees, not just 90 degrees to the clutch actuating rod but 90 degrees to the cable. I like to see it set up so that it starts on one side of 90 degrees and as the lever is pulled and the system moves it crosses 90 degrees and ends up just on the other side of 90 degrees. It is one of those things that is easier for me to say than type.
If the OP has an issue with getting the bike to go in or out of neutral he may be having a clutch drag issue. If that is the case less play at the lever combined with making sure the lever is at the right angle may help.