Self buffs should temporarily increase soft cap value

A little example (an example - no real numbers there):

If I had 1000 armor and the cap was 1100.

Currently if I used 500 armor buff, I would probably end up a little above 1250 for the duration, most of the buff over cap goes in vain.

But if the buffs temporarily increased the cap, I would enjoy full strength of total 1500 armor.

What is your opinion - should be full-strenght buffs reserved only for full-light armor characters or should every build benefit from them equally?

I think they already do that , or am I wrong?

Edit: sorry I was wrong https://help.elderscrollsonline.com/app/answers/detail/a_id/3565/kw/buff

Caps are there for a reason. For example, I think the armour buff that Dragonknights get is essentially to be used when in firestaff and light armour mode.

Why am I given abilities I should not use then?
If you are right and the ability was meant for cloth-only, why does DK has the ability then? If it is really restricted for cloth-only like you said, it should be abviable only in light armor tree then!

Because it's a DK ability; they didn't want it to be available for other classes.

Soft cap is ok, 1250 armor is still much better then the cap 1100(hypothetically speaking) and prevents people from stacking a rediculous amount of buffs for endless stat boosting.

Not every ability is effective for every build, nor are they all meant to be. Choosing higher efficiency with a lower baseline over the opposite is a strategic choice that you have to make, and if it isn't worth the tradeoff, you can slot something else.