As a cyclist who rides through the Jim Uffelmann park, I would like to provide some perspective from the other side of the off leash dog argument.
There is no doubt that some cyclists are inconsiderate. I see this both on the road and on multi-use pathways. I would ask, however, that we all not be painted with the same brush. When riding through said park, I slow down to jogging speed when passing people and dogs, and I ring my bell if I am not seen.
In spite of this, some pedestrians are also quite inconsiderate, as they will turn around and look at me after having been provided ample warning, but will continue to stand in the middle of the path and not move an inch to let me pass. Riding through the park is not always optional, as some previous commenters have suggested. It is a link between two parts of town for cyclists who would rather not take a detour via River Avenue and Griffin road.
While, like everyone, I have my own opinion about dogs at large in this space, the bottom line is that it has been designated a multi-use area and if we all show each other some respect and consideration we can all enjoy in safety.