Originally Posted by byeplane
...why turbofans are able to operate at vastly higher speeds and alts than a turboprop...
The turboprop-powered Tu-95 can do 510 kts (575 mph, Mach 0.87) at 40,000 ft. That's not exactly slow. In fact it's faster than the cruise speed of many turbofan-powered civilian airliners, and way faster than many business jets.