I've noticed the same thing, and it's one reason I don't like posting in the CO. Coming in at your big blind rocks in tougher games. It also means you can watch a couple of hands if there are any unfamiliar players.

If you normally miss your big blind, they make you post a dead small blind on top of posting a live big blind. If you get an option to post in the CO without posting the small blind, that's a win.

Posting a BB in the CO is much better thab posting BB+SB in the CO, yes.

But those aren't the choices. Let's say you come in UTG. Your choice is to post a BB in the BB, wait a hand and post a BB in between, wait 2 hands and post in the CO. If you come in after the BB but before BTN, you can post in betwren or wait one hand and post in the CO or wait an entire orbit and post in the BB. If you come in after the BTN, you can post in the CO or wait and post in yhe BB or wait even more and post in between.

Basically it comes down to how much you would have won in the hands you miss.

The big blind costs about -0.25 big bets, SB -0.15, BTN +0.20-0.30, and CO +0.15-0.20. I don't know what posting in between is but let's just say it's the same as the big blind. Posting in the CO is slightly negative, but because yhe baseline EV from the CO is high, it's a big hit.

If you ignore the rest of the orbit, you probably end up with an analysis around these lines: coming in on the BB adds up to something negative (-0.05), coming in between is slightly less negative (-0.05-0), coming in on yhe CO is even more negative (-0.10 to -0.05).

But the reality is that the rest of the orbit sums positive for solid winners. A 1 BB/hr winner will win +0.15-0.30 from the rest of the orbit. And that tends to swamp out whatever little bit of advantage that you get by waiting. So if you arrive OTB and your choice is to post in the CO or play with yourself for 15-20 minutes until the BB, LOL at waiting. If you arrive between HJ and UTG and sit there playing with yourself and then wave the BB by just to post in between, the tell you give off is worth way more than the EV you save.

If you just post at the earliest opportunity, you will end up posting your natural BB most of the time and CO some 9f the time and in between only 1/9 or 1/10 of the time at a FR table. If you play 150 hands per session you're only posting once, and let's say it's folded to you like 20% of the time. That's maybe once in every 200 hours this comes up.

And posting in between isn't allowed everywhere.

"Posting in the CO is slightly negative, but because yhe baseline EV from the CO is high, it's a big hit"

This part I don't understand. The whole idea behind posting IP is exactly that: you get to be in position. Being forced to play a random hand IP is way better than playing a bad/random hand OOP. It's a reason why there is some merit to straddling on the button. This means taking a smaller hit. Would you rather straddle UTG or OTB? Would you rather post money in the BB or IP? Same idea.

Being forced to play a random hand IP is better than being forced to play a random hand OOP, yes.

But if you play a random hand OOP you get to play a non-random hand IP as well.

You don't magically appear at the table when you want. You show up at the table and it's at more or less a random position (people tend to leave on the BB but depending how long it takes to get to thw table and whether people seat change, the open seat can be anywhere).

So you can choose to wait until the CO to post, but then you miss the BTN hand you would have gotten if you had posted in between. You can choose to wait until yhe BB, but then you miss half an orbit you could have played. You can also skip the BB and SB to post in between but then you don't get the BTN and it looks weird.

Exactly. Honestly, while I am open to arguments about it, I'm not even convinced the Mississippi straddle is +EV, at least if the game isn't shorthanded. Posting blinds is awful. Not only do you have to commit the blind, but it also then prices you in to play bad hands to multiple bets, and creates RIO situations post-flop when hands you would otherwise fold hit. (E.g., hitting top pair with your J2o that you would have folded.)

You want to play as many hands not posting a blind as possible. The way to do that is avoiding posting in the CO if you can help it.