Can Bitcoin transactions actually be reversed/"undone" by the sender by using/abusing the newish "replace-by-fee" feature? I am watching a live stream of Roger Ver talking about Bitcoin. Yes, I know that a lot of people violently hate him and I will say that I don't like Bitcoin Cash. I sold all mine for Bitcoin very early on, and it seems to me that bigger block sizes are a bad thing.
However, I must admit that many things that he said then and says now seem to make sense. I'm very open to the possibility that he's lying or warping the truth, but this in particular is something which stuck out to me:
Basically, he is saying that Bitcoin has been fundamentally broken on purpose by introducing the &quot;replace-by-fee&quot; feature, which, according to him, allows you to &quot;reverse&quot; (take back) Bitcoin transactions for minutes, hours and &quot;sometimes even weeks&quot; after it was sent.
Is there any truth to this? Is he purely making this up to cause fear and doubt? If so, please give me all the details.
My understanding of the feature is that it simply allows you to &quot;unstuck&quot; a stuck-in-memory-pool transaction by essentially throwing it a few more satoshis for the transaction fee, so that it will not be ignored but rather included quicker by the miners while a lot of Bitcoin transactions are happening at the same time.
Please let him be lying. Another thing that makes me doubt myself and my own understanding of the whole situation is what he says about the Lighting Network, which I agree is &quot;ultra-complex&quot; and &quot;never seems to come into actual use&quot;.
Basically, he is saying that Bitcoin has been fundamentally broken on purpose by introducing the &quot;replace-by-fee&quot; feature, which, according to him, allows you to &quot;reverse&quot; (take back) Bitcoin transactions for minutes, hours and &quot;sometimes even weeks&quot; after it was sent.

Not true. Bitcoin transactions with ZERO confirmations were always unsafe to accept as final. RBF just allows you to manage transactions in a better way because fee estimation is difficult in Bitcoin. For example: You can use any algorithm or manually check mempool stats and use a fee rate to broadcast a transaction but lot of other transactions broadcasted at almost the same time with a higher fee rate will decrease the probability of your transaction getting confirmed soon. If required you can replace this unconfirmed transaction with another transaction by using higher fee rate and fee.

Another thing that makes me doubt myself and my own understanding of the whole situation is what he says about the Lighting Network, which I agree is &quot;ultra-complex&quot; and &quot;never seems to come into actual use&quot;.

Its easy to use with wallets mentioned in this link: https://blog.bitrefill.com/top-11-lightning-network-wallets-bitrefill-328b5465b1b4
Exchanges: Bitfinex, Okex, Paxful, Kraken(soon), LNMarkets, fixedfloat, sideshift
DEX Protocols using LN: OpenDEX, OmniBOLT