Bingo! Yes, overcoming the bump, gives you a feeling that the resistance is somehow gone. But it's a spring, and it's resistance is always there, and always increasing.
The thing with reds is that it's a perfectly smooth, uninterrupted linear increase of force, so you feel exactly that.
With tactile switches, the bump distorts this feeling, there's a higher resistance in the middle, and when it gives way, you think the resistance is gone because your finger is already pushing down way harder than the spring's remaining force.
Regarding the question about the blues, just check the cherry wiki, there's graphs for all of these switches.