“HaGaon HaRav Elyashiv zt”l, HaGaon HaRav Smuel Halevi Wosner, HaGaon HaRav Shlome Zalman Auerbach, among other great gedolim all knew the psakim of the Shiltei Giborim and Ramah.”
anyone who considers these gedolim their poskim, by all means should follow their rulings. asey licha Rav does not mean that every time a gadol in e’y or anywhere else issues a psak, it is binding on all klal yisroel. Many other poskim are familiar with these rulings , and nevertheless disagree. Most importantly for me, my Rav, is aware of these poskim, and rules differently (because that is the kabbalah he has from his Rav and so on).