When editing the module, the following Calculated Property slows down VASSAL excessively:

If($TPPBC$ + $d12_result$<10,0,If($TPPBC$ + $d12_result$<13,1,If($TPPBC$ + $d12_result$<15,2,If($TPPBC$ + $d12_result$<17,3,If($TPPBC$ + $d12_result$<19,4,If($TPPBC$ + $d12_result$<21,5,If($TPPBC$ + $d12_result$<24,6,If($TPPBC$ + $d12_result$<27,7,If($TPPBC$ + $d12_result$<30,8,If($TPPBC$ + $d12_result$<34,9,If($TPPBC$ + $d12_result$<38,10,If($TPPBC$ + $d12_result$<42,11,If($TPPBC$ + $d12_result$<47,12,If($TPPBC$ + $d12_result$<52,13,If($TPPBC$ + $d12_result$<58,14,If($TPPBC$ + $d12_result$<64,15,16))))))))))))))))

Is there a way to simplify the above expression or is it possible to circumvent the expression evaluation process of the trait?