[recursive]

If you should slow down relative to the posted speed limit why not change the speed limit to reflect that directly?

[estearum]

Usually the reason is the "slow down" portion is very small, and it's confusing to shift down the actual speed limit for a 200 foot stretch of road then increase it again.

[Dylan16807]

There are signs for that. Advisory speeds that don't change the actual limit. https://wisconsindot.gov/PublishingImages/doing-bus/local-go...

Much better to be specific than a vague "slow down". There's a road near me with two tight turns a couple blocks apart. One advises 25mph and the other advises 10mph.

[recursive]

FWIW, it seems less confusing to me than longer speed limits, but with "Slow Down".

[alistairSH]

Except we do that all the time in school zones... normally 35+, but from 7am-9am and again from 2pm-4pm the limit drops to 25mph (which is still to fast if the kids are actually crossing the street or walking alongside en masse).