How could I cancel pre-processing and post-processing stages when training a neural network?

 [x,t] = simplefit_dataset;
 net = fitnet;
 rng(0)
 [net tr y e ] = train(net,x,t);
 NMSE1 = mse(e)/mean(var(t',1))  % 1.7558e-05

% WITHOUT DEFAULT MAPMINMAX

 [x,t] = simplefit_dataset;
 net = fitnet;
 net.inputs{1}.processFcns={'removeconstantrows'};
 net.outputs{2}.processFcns={'removeconstantrows'};
 rng(0)
 [net tr y e ] = train(net,x,t);
 NMSE2 = mse(e)/mean(var(t',1))  % 1.7241e-05