In a lot of ways playing on RP is very similar to the high stakes pro games you find on YouTube or elsewhere.
The reason for this is that it is always the same standard situations arising.
For example, you have pocket threes. The flop comes KK3. Whoopee, you have flopped a boat! However your opponent has pocket Queens. If a Queen or King falls on the turn or river, then your boat is sunk. (And if a 10 or Jack falls on the turn or river, your opponents may be able to fake a bigger boat than yours.)
These situations are pretty standard, but the difference in the high stakes games is mostly that the players spend a lot of time trying to determine whether opponents are bluffing or if they really have the goods.
On replay poker, players don’t think much, because they have little time to play, so they take a look at their hand, and they say “well I’m not folding that boat and looking like a fool if he is bluffing.” On replay poker a player will often shove the flop with their pair of threes, hoping that opponent with QQ will fold, which they hardly ever do.
Determining whether players are bluffing on replay poker is largely a matter of both knowing your opponent’s playing style and what they have done before, and to some extent making inferences from the size and timing of their bets, however it is perfectly possible to win tournaments on RP without calling any stone-cold bluffs.