Sorry I can't speak from experience when it comes to bridging with Proviron alone. I have bridged in the past but it was a combo of low dose Primo (200mg pw) and Proviron (50mg pd). Given the low anabolic component of Proviron I do not believe that by itself it would be enough for a true bridge??? Anyone???
In the past I have always used it in cycles with multiple other AS. Post cycle as part of bridge with another AS (Primo).
Or during the recovery phase with Clomid. Post recovery phase using Clomid and Proviron, I had my test level checked and it was 510 (as many know the normal is 300 - 1000). So at least for me 50mg pd had very little to no impact on my recovery post cycle...