Andre Villas-Boas was sacked because of his tactical inflexibility. Tim Sherwood should be wary of falling into the same trap.
Sherwood's switch to a 4-4-2 has been refreshing and effective, but it was always doubtful whether it would prove successful at Arsenal. Of course, after the success at Old Trafford, there was the temptation to keep the same shape, but it worked that night because Manchester United play a similar formation and are weak in midfield.
That game was there for the taking and Sherwood was right to go for the jugular. Arsenal, on the other hand, have the best midfield in the country. Every one of their midfielders is extremely comfortable on the ball, and when they have the advantage in numbers, it's always difficult to wrestle back possession.
It wasn't just the case of Spurs' two central midfielders -- Mousa Dembele and Nabil Bentaleb -- being outnumbered by Arsenal's central midfield three. Even their wide players have the tendency to come inside, leaving Dembele and Bentaleb with an impossible mission.
The latter has looked like a useful player since being introduced by Sherwood, but you have to question his selection on Saturday over the more defensively minded Etienne Capoue.
Perhaps it was a fitness issue, and in fairness to Sherwood, the players on the bench showed the paucity of options currently available to him. Tottenham are missing several key players right now, and who knows whether the manager's approach would have been different if he'd had the likes of Sandro, Paulinho and Andros Townsend fit.
As much as Spurs struggled to take control of the game, their extra numbers in attack did ensure that they looked dangerous when they got possession in attacking areas. Indeed, it was Christian Eriksen who was presented with the first real chance of the game as a kind ricochet saw him through on goal and his near-post shot was turned behind.
Unfortunately, that was to prove to be Tottenham's best chance. The final ball or finish just wasn't there. As the first half went on, Arsenal's control grew and it was no surprise when they eventually took the lead.
Kyle Walker came across to cover as Michael Dawson and Vlad Chiriches were dragged out of position, leaving space for Serge Gnabry to thread the ball through to the unmarked Santi Cazorla. The Spaniard made no mistake.
At 1-0, Spurs were still in it and perhaps Sherwood's philosophy would have eventually paid off. Instead, they shot themselves in the foot just after an hour, as Danny Rose tried to dribble on the halfway line -- despite being the last man back -- and paid the price as Tomas Rosicky dispossessed him, ran clean through on goal and calmly finished.
There was never a sense that Tottenham could get back into the game after that. The individual performances weren't there today, and as a collective they were always second best to Arsene Wenger's slick Arsenal side.
It says a lot that the headlines tomorrow will not be about the match as a spectacle, but rather an incident featuring Theo Walcott. The Arsenal striker was stretchered off and while absorbing abuse from the Spurs fans, he held up two fingers to indicate the score.
The coins came raining down and Twitter erupted in pious fury, ignoring the fact that if it were a Tottenham player who had done the same thing, a statue would be erected in his honour. We fans dish it out to players and it's a bit ridiculous to act mortally outraged when they give it back.
Instead, it's better to concentrate on the actual game and what it might mean. This result isn't a disaster, as painful as it may seem right now; no one wants to go out of the FA Cup. But when you're drawn away to the league leaders, you go into the game in the knowledge that it may well happen.
I would love nothing more than for Spurs to win this competition, but there's no point pretending that an early exit won't make the team's league campaign a lot easier. Yet if there are positives that can be reluctantly dredged from the result, only time will tell if the manner of the defeat will prove significant.
Tottenham just sleepwalked into a loss that was predictable for those with their eyes open. Will Sherwood wake up, or is he destined to prove himself to be more similar to AVB than he first appeared?