What is the test for determining whether counsel has made a tactical or tactical decision in a civil case?

investigate must be directly assessed for reasonableness in all the circumstances, applying a heavy measure of deference to counsel's judgments"). "[S]trategic choices made after thorough investigation of law and facts relevant to plausible options are virtually unchallengeable." Strickland, 466 U.S. at 690. A disagreement with counsel's tactical decisions does not prove that the representation was constitutionally deficient. United States v. Mayo, 646 F.2d 369, 375 (9th Cir. 1981) (per curiam).