Time to reduce troop training time?

Now all spells are capped at 20 mins, shouldn't the 45 mins troop build time also be reduced to 20 mins?

I think some plausible argument is: there's only 1 spell factory but more than 1 barracks (2 or 4). HOWEVER, a lot of time I just build 1 stupid pekka as a donation troop. If SC allows me to "combine" all barracks to build the same troop, then I'll be fine with the current 45 min time. Otherwise, it's really a flaw to think people are always going to build 4 (or 2) same troops with all barracks..

So either all 20 mins, or allow barracks to be combined. How about that?

There's only one spell factory, but 4 barracks. So, I don't anything will change...