As technology advances so does the ability to drill deeper and more complex 3D wells. The costs associated with these wells have also increased significantly. In an effort to minimize non-productive time (NPT), one key learning is that utilizing surface parameters alone for decision making is unreliable. To perform many operations, access to real-time downhole parameters can be the difference between a successful or failed operation.Historically, pre-drill modeling and surface parameters were used for decision making during operations; current technology now allows access to real-time downhole parameters to improve the quality of the information. Understanding real-time downhole parameters can lead to more informed decision making, minimize operational risk, increase operational efficiency and eliminate unnecessary capital expenditures.This paper describes recent activity in a deepwater subsalt development well involving a very difficult bypass in the 10 3/4 inch ϫ 9 7/8 inch production casing in which a wellbore intervention method that records and makes use of real-time downhole parameters is utilized. This paper will discuss different stages of the bypass operation where real-time downhole parameters; such as, torque, weight, RPM and bending moment were utilized in making real-time operational decisions. During an operation where the real-time downhole parameters were disregarded an unsuccessful operation resulted.The stages of the bypass operation to be discussed include: Drilling:Completion:1. Compression testing in the 10-3/4" x 9-7/8" x 7-3/4" production casing with water-based mud and ZnBr fluid to optimize completion BHA's.As drilling, completion and wellbore intervention operations continue to present technical and economic challenges for deepwater operators, using real-time downhole parameters in combination with surface parameters will improve operational results. This paper will demonstrate the use of a drilling mechanics Smart Intervention system and service that helped improve the overall success of a bypass operation.