I'm afraid I can't replicate your results. The buffs I use for my comparisons are:
Over-TP Rnds 0.35
Ionis up
Tojil
10% Defense Down
RCB
Frailty 37.1%
Fury 44.9%
Torpor 44 evasion down (Entrusted)
Haste
Boost-STR 500 skill
2x March +5
1x Madrigal +5
1x Minuet +5
Berserk/Aggressor/Hasso/Overwhelm/Meditate active
Meditate Over-time 10
Meditate Merits 1
Zanshin Merits 4
Under these conditions, the new set beats the old set by 4-5 DPS.
As for the leg/feet swap,
just in this situation, I do get Sakonji Sune-ate +1 *just barely* ahead (like 1 DPS more, or .0006 more) of 2 DA Otronif feet, but Wakido Haidate +1 still lose out to 2 DA Otronif legs.
Ultimately, though, the difference between the few couple swaps is so miniscule I wouldn't say someone is "bad" or "wrong" if their set differs slightly. The smallest things could change the outcome of some pieces and you may find things slightly better or slightly worse than what's in the OP depending on your buffs. Do note that the sets in the guide are not saying "you
must shoot for this to be the best". As the saying goes, it's all situational.