fwiw let me add, that I think many of these players were smart, capable, winning players.  I'm not trying to insult live MTT pros.  However I think these bet sizing decisions could have more to do with a particular MTT zeitgeist instead of proper analysis of these individual spots.

I brought this up in another thread here a few months ago. Noticed the same thing when I had a tourney spree and played a bunch of tourneys online. Bet sizing in all positions and situations were at times extremely off. Like consantly min 3betting OOP or just cbetting extremely small on drawy boards etc. Also yesterday a some what famous toruney player joined my regular Rush tables and he was playing the same way in cash games which made him very easy to play vs. 

My take on it is that tourney players have developed this style based on small stack poker and it's just something that has caught on. Also I suppose it works fairly well vs a lot of players who just play fit/fold and don't really think about the bet sizes. But I'm guessing this will have to change in the future when players evolve. 

MTT post flop poker just doesn't play "normally" and it'll give you cash gamers a migraine.

I think you can definitely succeed with smallish bet sizing when done correctly.

A lot of brain dead regs will just say "makes bluffs cheaper" when asked why they do it. I think a lot of them began to parrot what they saw good players doing without understanding the When and Why of it all.

Draw heavy boards are where I see the most mistakes, as you'd expect. Not only do you give people correct drawing odds but some regs will induce flips they shouldn't really want to take, when instead they should be wanting to make the hand end on the flop or turn for obvious reasons.

The good players use their small bet sizing in correct situations to induce poor bluff, get people to turn hands into bluffs, and generally control the pot size and confuse their opponent.

But like any game, there are way more button clickers than thinkers so that's what you're seeing.

I always lol when no one changes their opening size or 3 bet sizing to account for stack sizes and positions at the table.

I hate to use Isildur as an example because he's world class, but there's a guy who uses cash game sized betting (mostly) in tournaments and absolutely kills it.

I don't railbird much anymore these days and when I do, it's only 1 or 2 players so I can't think of anyone besides Viktor to use as an example.

This isn't just a thing live MTT pros do. I think people got it in their head they can cbet super wide and super small and autoprofit a lot, which they can do vs. weaker players, but can't do vs. stronger players.