Roy Jones never "put up 30 lbs and lost them" , more like 2-3 lbs , 5 at most , if at all . He simply did not dehydrate against Ruiz , or he did , but not close 2d Xtent he did 4 his fights at 175 , that simple .
U really think he cut only 10 lbs of liquids ? maybe during his 1st year or 2 at d weight , but not later . If he had , then d mid 180s was probably post diets and fully trained 2d max only left was 2 dehydrate . Against Ruiz he did not have 2 diet nor dehydrate 2d max , he needed some mass so he wouldn't b pushed and bullied around more than what he could endure . But anyway , even according 2 your post , which i disagree with , he only had 8lbs "2lose" when he had 2 come "back down" 2 lightheavyweight . Tarver was more drained fighting Jones than Jones was fighting Tarver . Also Tarver was/is older than Jones and was past drug abuse whereas Jones was not , plus Jones had more almost harmless "professional experience" than Tarver .
Jones was 31 vs Hall . Maybe he dehydrated less than I thought pre Ruiz . But other lightheavyweights usually cut more weight and dehydrate more than he had 2do in each of his fights vs Tarver still . And again , Jones lasted 12 with Tarver "immediately" after "coming back down 2 175" , as if he didn't have enough time 2 prepare and cut d weight . It was his 2nd fight against Tarver in which he got his azz KOd . And even years past it he even made 175 and once even 170 . Do not blame his loss 2 Tarver on Roy's "heavyweight" stint .
Roy Jones Jr. fought at 160 pounds with a same day weigh-in back in 1993. Can't have been easy for him.
You do go gain over a pound of weight when you drink a pint of water. It is just water and it will be pissed out soon enough, but the number on scale will move up, which was Armstrong's aim.