By James DuMars As the commercial mortgage banking market has been discussing for the last few months, CMBS as a debt vehicle is essential to the functioning of our real estate capital markets. However, it is important to grasp how vastly different CMBS is from a portfolio loan at a life insurance company. When it comes to the choice between the calm life company environment and CMBS, there is just no comparison. For example, during the period when spreads were blowing out, one of my clients locked rate on a 50% LTV for a grocery anchored retail center with a…