If I understand your question completely,
With my Breweasy system (about 5 years old now) there is consistently a 3F temperature drop between the sensor element for the controller and the MLT. This may vary slightly depending on how long your silicon hoses are cut, flow rate, ambient temperature etc.
YMMV, but if I wanted to mash at 152F, I would heat all the batch water to a temperature that would yield 150F after mash-in. For most of my batches I use about 11 pounds of grain. For my system, that equates to 161-162 F strike water to reach 150F mash-in. Then pump just enough water to the MLT to cover the grains. The difference in a mash-in at 150 vs. 152 doesn't seem to make a difference. During the 10 minute mash-in rest, recirc the BK with temperature SP of about 155F, to account for the 3 degree system temperature drop. BK water temperature will not drop this low, but once recirc through the MLT is established, it will.
After the initial 10 minute rest, establish "normal" Breweasy recirculation. Any temperature overshoot will only occur at the surface where the heated water enters, and the mash will come to equilibrium at 152. As always, adjust next time if needed. Describing the process is more difficult than it is to perform.
I hope this helps, and good luck!