Yes if you only want girth do only girth work.
Pumping gains are permanent. Well at least for girth in my case. I never pumped for length like some of these guys do.
The real trick to pumping is watch the fluid buildup. There are guys who are claiming big pumping gains that are not cemented. It’s all fluid build up. All my pumping info is at least 3 years old and may be old school way by now. So I would read that forum before pumping.