I was so confused about "Attack Speed". Why TOV and stationary effect is same?

I was doubt about the unit description which stated that stationary could give Streltsy 30% attack speed. So I doing a research.

Unit attribute info showed Streltsy have 2.12 attack speed in initial and increased to 1.83 with max stationary effect.

An attack speed test was performed by attacking a building, 10 Streltsy with 700 hits was complete in 131 seconds, which indicate it’s attack speed is actually 1.87(131/70).
I guess this may caused by the attack animation, cooldown(1.83) and attack(0.04). For example, when a bombard was cooldown, it won’t attack instantly, instead, it will preform an animation then attack, so that cost extra time.

But what ever, the more important to me is “Do stationary really give 30% attack speed?”. But this is hard to test with streltsy because stationary effect get increased every 5 second.
But! The “Tower of Victory”, landmark of Delhi, give nearby infantry 20% attack speed, so I turn to test this effect.

VERY SURPRISED, I found when a handcannoneer get close to Tower of Victory, it’s attack speed increased from 2.12 to 1.83, which exactly same with a streltsy get max stationary(30%).

So I got more confused… 20%? 30%? I don’t know how to understand that 20% was equal to 30%.

I decide to compare the actually attack speed by two unit attack a building in the same time.
Two handcannoneer, A and B, A with TOV effect, B without TOV effect.
The attack sequence was: AB, A, B, A, B, A, B, A, B, A, B, A, B, A, B, A, A, B, A, B
When B attack 9 times, A already attack 10 times, which means attack speed actually increased was between 11.1% to 12.5%, not 20%, not 30%.

So I got more and more confused… It’s even a lie? only 12.5%?

Then, I do the same test with archer.
Two archer, A and B, A with TOV effect, B without TOV effect.
The attack sequence was: AB, A, B, A, B, A, B, A, B, A, B, A, B, A, A, B
When B attack 8 times, A already attack 9 times, which means attack speed actually increased was between 14.2% to 16.6%, not 20%, not 30%, not 11.1%, not 12.5%.

So I got more and mooooooore confused… Why the same effect has different effect on two unit?

Delhi have 5 infantry unit, which one is the most effective to the TOV effect, and which one is the most ineffective?