Because of its well-documented effectiveness in enhancing strength and ductility of unreinforced masonry (URM) construction, Fiber Reinforced Mortar (FRM) is now widely used for consolidation of heritages, such as churches, palaces, castles, and entirely historical centres. The main purpose of this work is to provide the authors' principal outcomes in the FRM application to masonry after performing extensive experimental campaigns and numerical simulations over the previous few years. The recent findings have already been appreciated by the research community but have been yet to be considered into existing standard codes/recommendations, leaving the contribution of fiber mesh (i) and features of both coating mortar and URM wall (ii) to the improvement of the shear strength of reinforced masonry panels unclear. In fact, unlike FRP, fibers embedded in the mortar coating of the FRM do not affect the shear strength of the reinforced panel, "limiting" its effect in enhancing the load-bearing capacity of the wall and, therefore, the structure's ductility. This important recent experimental/numerical evidence should be introduced in the code’s recommendation avoiding overestimating the FRM performance during design phases. Furthermore, the Italian codes suggest simplified amplification factors for estimating the improvement of shear strength owing to the strengthening system that ignore the fact that the greater the thickness of the masonry wall, the lower the FRM's efficiency, and vice versa. A practice-oriented analytical formulation has been provided to validate such mechanisms by confirming a consistent data set of masonry panels strengthened by FRM tested under diagonal compression. In this work, a numerical investigation is provided to highlight the importance in considering the effective thickness- and tensile strength- ratio between FRM mortar coating and the URM panel to accurately predict the enhancement in the mechanical behaviour of the FRM-reinforced masonry.