Guys I'm really not getting it.
From previous posts it seems like if I try to burn constantly the coins I'm minting with PoB (reinvesting the profits of the previous investments) I have to create a new wallet each time, but it this way I'll do not have any profit of the previously burned coins any more, right?
No, creating a new wallet for every "burning" is not necessary. But if you want to stake coins via PoS, it's better to use a separate wallet for it than the one you "burn" coins via PoB wallet if you have low computing resources.
Does it mean that those with a consistent quantity of burned coins will still receive returns?
BitcoinFX's post was (as I interpreted it) about a distant future where you would have to burn coins with a high value to be able to profit from it. For now, we're far from this point. But if Slimcoin is valued 10x higher and you can conserve your "Effective Burnt Coins" from now until then constantly burning more coins then you probably will be still profitable. But there is no guarantee.
I, for example, have about 3000 burnt coins and I got them back approximately in 2-3 months and from then on all was profit. Like gavrilo77 I wasn't minting 24/7, but let's say 50% of the time, so I could have got the investment earlier.
But if I fraction them into different wallets/clients I'll never have a consistent quantity of SLMs in one place, thus never receiving any return, right?
No. As far as I understand the whitepaper, you have the same probability to find PoB blocks if you have three wallets with 3000 + 4000 + 3000 than one with 10000 SLM. Only that you will have to run all three wallets.
The other thing that I hardly understand, if I had a big quantity of SLM and would decide to burn them all, I'll never get returns, as someone stated previously? So what is the right quantity of coins to burn and why?
That depends on the quantity of coins burnt by all users and on the burn difficulty. Burning could get unprofitable for an individual if this quantity is very high - or if suddenly after his "burn investment" the quantity of burnt coins by all users increases drastically.
If, for example, you burn 100000 coins and all other users also have 100000 "effective" burnt coins, then you have 50% of the "burn power" and will mine about 50% of all PoB blocks. But imagine other user decides some blocks later to burn 200000 coins. He will reduce your "power" instantly to 25%.
So burning is always a investment with some risk. If you follow the "Formatted nEffective Burn Coins" number (type "getburndata" in the debug window console) then you have approximately an idea how "popular" burning is. If burning is popular (higher amount), it's more risky; if it's less popular, it's easier to become profitable. In a mature market an equilibrium is probable, but we still don't know which is the "ideal" number of burnt coins (by all participants)
The example I outlined above (about the 3000 coins burnt that I got back in 2-3 months) was in a moment where the "Formatted nEffective burnt coins" score by all users was about 800.000. Now it's already higher, so you will get back your investment later or will have to burn more coins.