Digital BW, The Print

In order to achieve a decent contrast range in any of my prints (on 
EAM or Photorag & MIS inks) I always have to duplicate the Background 
Layer (with varying opacities) and set the Blend Mode to Overlay. 

If I dont, I never get a decent contrast with a good black tone. To 
try and give you a "picture" - in traditional printing I favour grade 
3 or 4 rather than grade 2 or 1.

Is this a perfectly acceptable method of working or am I doing 
something wrong further up the line. Are others using the same trick

thanks
Frank