I don't know why you are arguing against having both? It doesn't hurt you in any way if I choose to do it the way that is easier for me. Also Let me explain in reply to your comment below why it is easier for me.
I can, at any time out of combat, look at a teamate's items. From this I can see their health/mana. I mentally have a catalog of how much of each of those resources any champ needs to be able to participate depending on the situation. This is done all out of combat in a non stressful time when it doesn't matter if it takes me a bit longer to go through it, because it is mental preparation before hand. Then when there is a stressful situation where I don't have time to click on an ally and see just how much health/mana they have I can just glance at their bars and know from the percents.
In other words my method is:
- Before hand mental prepping (Knowledge of how much mana/health % an ally burns through in combat & their items influence on that)
-In combat-
- Look at ally bars
- See the % they are at
So it is only 2 steps when it actually matters.
Your method is:
- Before hand mental prep (Knowledge of how much mana/health someone uses in flat amounts)
-in combat-
- Click on ally
- Read the number of each of their bars
- Know if that is enough
(I separated out the step 3 for me into 3 & 4 for you because it takes longer to comprehend a specific number and compare it to a general number in your head than to go "They are at 1/4 mana? That is enough")
So while my method DOES take more before hand mental prep it is actually much faster in combat AND I can do it while attack someone else which you can't do since you have to click on your ally. This is why we don't have numbers above our heads, we have bars, because it is easier and faster for the human brain to work with values like 1/2 or 1/4 or 1/5 than values like 262 mana.
So yes, in combat it IS easier for me. Also remember that easier isn't just number of steps. It is a lot easier to do an equation like X = (53^2)63 + 12/A where A is 7/13 than to imagine a new colour. Our minds are perfectly capable of both, and one is only one step, but it is basically impossible for our minds to comprehend because our minds don't work that way.
People's minds work in very different ways. Some people have to have visualization of something to easily understand it. Some people need it to be said out loud. Others learn through stuff that is written down. So don't say what is and isn't easier for everyone. As I clearly stated, my mind comprehends and compares percentages much more easily than flat numbers, so for me it is both a faster process and an easier one because that is what my mind is good at. I promise you it would take me a couple times longer to do it your way than my way.
Also you clearly misunderstand how I am getting my percentages. I don't have to look up flat numbers and convert them. I straight up just know from experience how quickly every champ in league burns through mana. When you watch people burn through mana you aren't watching the amounts of mana they are using unless they are very low and you are watching to see if they have enough mana to ult. You watch the speed at which they burn through mana and from that know whether they have enough mana to combo. I also know how much different mana items increase mana pools by, and as such can easily factor that in.
it is nothing so complex as looking things up. I just know how much of their mana champs use.