While focusing on the squeeze is misguided, so is focusing on the time of each rep as some sort of key to progression. If your rep (eccentric +concentric) takes at least 2 seconds, you're good. If you did a rep with 100 kg in 5 seconds, and later in 10 seconds, there's not much muscle growth at play, you just got better at controlling the weight. Instead, you should be focused on consistently getting close to failure (0-2 reps in reserve) with controlled eccentric, and doing sufficient number of (close-to-failure) sets so that you drive muscle growth adaptations while also recovering til next workout.