Congestion is three matches in eight days — cup midweeks, continental travel, December pileups. Effects are measurable: rotated line-ups, a slight drop in high-intensity output, and modestly fewer goals from tired legs late in pileups.
The betting relevance is timing: prices set early in the week can lag confirmed rotation, and player-market bets (scorers, cards) are the most exposed to a name simply not starting. Check confirmed team news before anything congestion-sensitive.
A side playing its third match in seven days, post-European travel, rotates four starters. The 1X2 barely moves (the market prices the squad), but the striker priced at 2.10 anytime is on the bench — the bet died at the teamsheet, not at kick-off.