i think it's great what IVCPA (Idaho Velodrome & Cycling Park Association) has accomplished. Lots of volunteer hours have gone into building features for bikers who want to jump, jam downhill and otherwise challenge themselves. i believe that these folks need to have an appropriate place to ride the way they want to ride, and this park is growing into what appears to be a nice venue for them.
rabbit run is the one ridge to rivers trail in the area and it connects to big springs, veteran's cemetery and hopefully in the future to avimor and other yet to be developed trails. rabbit run, rei connector and all trails above the cemetery are currently off leash.
it is especially important to follow the rules in this area because failing to do so can cause serious bodily harm- to a dog or to someone on a bike or both. this jump goes over the trail, and any loose dog below would be seriously injured if someone came flying off.
in other areas, dog are supposed to be leashed because bikes can and will be flying around corners, over berms, etc. pretty much not what i would consider a relaxing trail experience if busy.