For me it has to be as little as possible and if I do I try to avoid times when everybody else does it! On most lakes you will notice that most people will recast at dusk and dawn and nearly everyone will be doing it at the same time. I think that these times are the prime bite times and the last thing I want to do is to disturb the area.
Once I have cast out and I am happy with the location, have felt the lead down and am happy that the rig did not tangle on the way out then I am quite happy to leave it where it is for between 12 to 20 hours. I will generally wind the rods in and have a walk around the lake and have a chat with other anglers etc. In most cases I try to do this between 12 and 2 but apart from that once I have cast the rigs out I will leave them where they are. If I am tempted to recast I always ask myself “why?”, if I cannot come up with a very good reason that I should I resist the temptation to do so.
I know that this is generally not the norm but I do have my reasons. First of all I believe the less disturbance the better. My baits are in place and ready for the prime bite times and how many times do you read in the magazines etc that washed out baits trip up the most wary of Carp? My hook bait that has been in place for 10 hours sure does look and smell like all the free offerings a lot more than that freshly cast out rig and bait.
I have to admit that I used to recast a lot more than I do now, but hand on heart I am sure my catch rate has improved 100% by adopting this approach. It is not the right tactic all of the time and it also may not be the best but it works for me so give it a go and let me know how you get on.
All the best