SoftwareSerial with ATTiny84 using ATtiny library

I think the Knock-Bang example can be reduced to this...

#define KNOCK_BANG 1
#include <TinyDebugKnockBang.h>

#ifdef KNOCK_BANG
#define Serial Debug
#endif

..then you just use Serial...

// the setup routine runs once when you press reset:
void setup() {                
  // initialize the digital pin as an output.
  pinMode(led, OUTPUT);  
  Serial.begin( 9600 );
}

// the loop routine runs over and over again forever:
void loop() {
  digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);               // wait for a second
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delay(1000); 
  Serial.println( "Testing...");  // debug output
}