The version 16 of Maple does not know the function "pow", it is replaced by "power". Nevertheless, the codegen[optimize] procedure still generates it!  Moreower, it's not optimal even to write poser(..., 1/2)  as, most probably, the function sqrt must run faster. 

  Here's an example: (the function being optimized just contains some nested square roots)

> iang10 := [codegen[optimize](Re(int11), tryhard)];
[       2        t17                                   
[t17 = q , t14 = ---, t24 = t17 vF1, t11 = -t24 + t14, 
[                m1                                    

                             2      
  t13 = -2 I omega, t25 = vF1  t17, 

           /                           1\  
  t20 = pow|4 t25 - 4 (t13 + t24) t11, -|, 
           \                           2/  

  t21 = 2 (q + t17) vF1 - 2 t14, t22 = vF1 q t20, 

                                            /              1\  
  t23 = 2 t11 (t13 + t14) - 4 t25, t19 = pow|-2 t22 + t23, -|, 
                                            \              2/  

        1                                  /             1\  
  t3 = ---, t27 = (t20 + t21) t3, t18 = pow|2 t22 + t23, -|, 
       t19                                 \             2/  

        1                                  (1/2)   / 1         
  t2 = ---, t26 = (-t20 + t21) t2, t1 = 4 2      Re|--- (q t11 
       t18                                         \t20        

                                                              \]
  (t19 (ln(t26) - ln(-t26)) + (ln(-t27) - ln(t27)) t18) t3 t2)|]
                                                              /]