"our hospital is trying to come up with a plan to have solely primary care nursing, instilling the thought that nurses SHOULD TOTALLY CARE the asigned patients, including meds, carrying orders, vital signs taking, and other request peratining to their assignment. Added, to that, the load to be given includes 10-12 patients."
This sounds more like the Total Patient Care Model. In this model the nurse is responsible for what you are describing, total care, and is often referred to as primary care. This model is best in areas that require a higher level of expertise with patients with high acuity. This model only works with limited numbers of patients like in a critical care 1:1 or 1:2 setting.
If your facility wants a true primary care system 10-12 is too many patients. I believe a team approach would work better. Realistically, a mix of approaches is what many do and according to various factors, staffing, types of available staff, census, acuity, etc. In my experience primary nursing is planning, managing and coordinating a patients care with off-shift nurses carrying out your plan of care. True, the primary nurse is direct care and closely linked to the patient but other care needs can and are done by other staff (i.e., LPN, CNA). But, perhaps it was more of a modified approach. No need to be to rigid.