Were the stealth rock mechanics changed over the generations?

Question

In gen seven, if you have an odd number of hp, stealth rock damage is rounded down. If you watch False Swipe Gaming's Charizard video, it had 297 hp and died to two stealth rocks. First entry did 148 damage and the second one did 149. So, did stealth rock damage work differently in gen four? If yes, then when was it changed to round down?

Comments

Here watch these two. I watched the video as well, doesn't make sense. https://replay.pokemonshowdown.com/gen5ou-1215419566
https://replay.pokemonshowdown.com/gen5ou-1215420188
I tested it with 2 charizards, one with no hp evs, same as in the vid, and one with 248 evs, cause I thought maybe no evs was specail or something. Either a, the video was wrong or b, showdown is wrong. Oh and, I think that was gen 5 so I tried gen 5

---

According to Bulbapedia, no.

---

odd number hp charizard should always be able to switch into stealth rock twice and still have 1 hp regardless of the generation. that much hasnt changed

---

@SleepyDreepy that was on gen four actually. That video didn't cover gen five due to lack of notable change

---

Can you challenge me to test? My name is SwastikMis123.

---

How do you do that?

---

Huh? Just go to "Find User", enter my name, then challenge me.

---

Alright I'll give it a try right now

---

Oh says you're offline. We should organize a time for this though

---

I wouldn't be online today, sorry. Tomorrow, but can you tell your username?

---

It's alright. You have discord? I'm using a profane username and I think I'm gonna piss off the mods if I comment it here. My tag and username on discord is Apex PredatoR#6190

Answer 1

What ☆SleepyDreepy☆ says is correct. I'm not sure whether PS! has different mechanics from Pokemon Games, or it was a glitch or bug. According to Bulbapedia, there has been no changes in damage modifier in the generations. See the changes:
Gen V
> Stealth Rock can now be reflected by Magic Coat.

Gen VI onwards

Defog now clears Stealth Rock from both sides.
Stealth Rock is unaffected by strong winds. In an Inverse Battle, Stealth Rock uses the inverted weakness and resistance to Rock to calculate damage.
Stealth Rock can be used as part of a Contest Spectacular combination, causing Circle Throw, Dragon Tail, Roar, and Whirlwind to give extra three appeal points if used in the next turn.
Any Pokémon that appear after calling for help during SOS Battles are subject to Stealth Rock.
If powered up by a Rockium Z into Z-Stealth Rock, it will raise the user's Defense stat by one stage.
Using G-Max Stonesurge will set up Stealth Rock on the target's side of the field.

Source

I would want to test it myself, but right now no one is free and I can't challenge myself.