Those retards should be asked how small should the infinitesimal
interval be so that they can fix a local inertial frame on it.

I blame cheap education for this retarded behavior. Often in cheap
schools some teachers will use the infinitesimal method to try to
explain to a group of students whose highest IQ is below 100 how to
understand geometrically accelerated motion: Break down the path to
small infinitesimal intervals, then take the differences, divide by the
infinitasimal time and take the limit.

God forbit the retard of sci.groups thinks this is a method he can use
to incorporate accelerated motion in SR. This is because that is all he
knows. Consider a mass m in free fall near the earth surface to see
what he essentially does:

s = gt^2/2   (1)

let s ---> s+ds    t ---> t+dt

(s+ds) = g (t+dt)^2/2

Expand and simplify. You get:

s+ds = g [ t^2 +2tdt+(dt)^2]/2 or given (1)

ds/dt = gt + dt/2

I am asking the retards now: how small they want the dt to have
constant velocity ds/dt?

He is such a retard that he cannot understand that even if he lets
ds--->0, still ds/dt = gt, far from a constant unless the clock in his
stupid head stops ticking, which appears to be the case.

One exception: at Planck time level, the ds--> 0 can give rise to ds/dt
= constant between Planck intervals but of course you have HUP there
and you are not able to fix the local inertial FoR.

Mike