Not sure what you are asking? If its that you want separation from other visible traffic to Radar during your descent in IMC that is one thing if you want a cloud break remember that off a published approach you can only come down to the MSA for the area you are in and all radar can do is to confirm where you are in that descent and that you are descending to the right MSA and not in the wrong area where the MSA might be higher.
Pace