First of all...I don't understand why we are still sticking to the point that old content is not to be replaced by new. EVEN if it was SE's "way of doing" things pre-abyssea (which I don't think it's fully true).. it needs to be changed and is SE direct intention to have it changed b/c of all the issue the community has reflected on SE about waste of time (time grinding) in 1-3 camps.....

so you need example of here fully replace then here it is:
Sarutobi Kyahan (Haste +3%).. once thought to be the best TP piece for MNK/SAM/NIN is fully replaced by Fuma Sune-Ate (Haste +3% HP+12 AGI+3)
so there you have it.. to counter what you say about there isn't a single piece replaced... if your argument is there are still useful gear pre-75 (pre-abyssea we talking about) that is still good @ 75, then of course, any player should knows that already.. but your argument is SE never intent to replace old gear.. that is totally false
in case you say not enough example and that you want something about relic replaced
Healer's Cap fully replaced by Yigit Turban and/or Goliard Chapeau
Wizard's Petasos replaced by Demon's Helm or +1
Myochin Sune-Ate (for evasion in case you need it) fully replace a few feet evasion gear ( one comes to mind is one that offer +6 evasion and parry skill, can think of name at the moment)

Again there are many more, but I'm not gonna waste more time looking.. and more over, stop contradicting yourselves with 5/5 set have to replace 5/5 of another set, and then go and say not using 5/5 but mixing in is better most of the time, b/c yes it's true that mixing gear mostly is best for any given job, which is exactly why we look at individual piece being replaced, not a full 5/5 set being replaced by another 5/5 set.

SE thank you for changing your way of doing things (more time grinder = better geared player) such that we no longer need to grind time everyday to get that 1 or 2 great pieces, b/c now we have better piece of gear to get that isn't a time sink anymore.. ignore the good-old-day-er that just can't take changes.. changes for the better!