I think its more meant in the sense of "100% faster" which would translate to twice at fast which means contruction time shortened by 50%
exactly not going to make it magically spit out units in 0 time.
The exact opposite is true of logistics... it says 150 pct but is really 250 %. As yTebru said its +150% faster. So 1.00 speed x 150% would be 1.50 but in reality you get 2.50 speed (base plus 150%) which is actually a 250 pct increase even though it says 150 pct.
Maybe it would clearer if they stated the inverse and labeled "Mobilization time with": 90%; 80%; 70% 60% 50% so a 20 hr build would be 18; 16; 14;12; 10 hrs
Thanks @Kranzegrad - and I just had to laugh after looking this up myself!
In fact I believe you found a nice little UI bug... It should read "+(PLUS) 25%" or "+100%".
Actually, the way we spell the benefit in the building description players seemingly GET PENALIZED for building it. eg. RecOffice Level 1: 25% Mobilization Speed would mean you now only mobilize at 25% speed. Only at level 5 would players reach normal 100% according to the description.
Sorry for this confusion... Will add to fix list.
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