frankly, i doubt that this overload is “real”. I think it is a parameters mistake. So, yes, you can downtilt the cell : you will loose coverage, you will loose traffic. Loosing traffic = subscribers out of coverage = loosing money. Your boss and your subscribers are going to be very happy about that 🙂
I don’t know hat’s the name of the S parameter.. can you check your dictionnary of parameters and search for all parameters related to Channel Requests ?