Most know that the 757 requires a large amount of thrust to be used to start gaining speed while taxiing in IF. Today I just happened upon a way to circumvent the 757’s taxi bug and actual gain ground speed while using idle thrust. This workaround works both before take off and after take off. The effect of the idle thrust on acceleration depends on your 757’s weight and if you are turning or not.
To taxi the 757 without losing GS at Idle thrust just pull down the progressive taxi to anything below 30% brake. The result will be that you should see the aircraft gain GS. Using the progressive braking overrides the bug in the 757 model that forces you to need 35% thrust to start gaining speed on taxi. Once you start applying 50% brake you should start to slow down as normal in other aircraft models with the progressive braking feature. The effect is the same on turning, although normal turning physics apply and you might need to add 10% thrust to actually accelerate but not certainly less is needed than the 35-45% thrust without using progressive breaking.