Normal mode as Heroic mode and Heroic mode as impossible mode

[Deleted]

Only if you bring mostly heroic raider alts.

This.
Normal mode is pretty challenging if your group can only invest 3-6 hours a week. This is not bad at all. Some encounters are hard and need training to get into the routine.
ToT will be PUGable if enough casual players have the experience that is needed or if enough overgeared/experienced people are in the group that trivialize the encounter.

If you want the easy mode. Just do LFR. That is what LFR is for.

[Vakna]

I don't know what game you're playing, Normal modes (all of them) and some Heroic modes are harder than they have ever been in WoW this tier.

If Blizzard did what you suggest the bosses would be pretty much mathematically impossible to kill, and maybe only 1 or 2 guilds in the world would ever completely finish a tier on heroic. Do you honestly think that is good business practice? Or in fact what anyone actually wants at all? Blizzard will never ever ever create content that applies to only 100 people out of 8+ million of their customers, you literally have more chance of walking outside your house right now and getting struck by lightning, twice.

If you really believe this would be a good idea, I strongly advise you to never put yourself in a position of product responsibility - it wont end well.

[Venant]

I also think that its about time people start running 3 minute miles, because waayyyyy too many people have run 4 minute miles. Personally I think I once ran a mile in like 7 minutes, but its not like that is at all relevant, im sure i could have run a mile in under 4 minutes if i simply ran twice as fast!

[Chickat]

You can pug 10 or 25m as it is.

Not on my server.

[Deleted]

Not on my server.

yeah.. you can't really. At least I cannot imagine a lot of pugging working. In fact.. I have seen exactly 0 pugs this tier; ToT is so pug unfriendly.
ToT has a ton of awareness and "retard" checks. Do those wrong and the whole raid wipes. In fact it is easier to kill something 9 man than it is to take a bad trial with you even.