No, for IR protocols like RC5, which are bi-phase encoded, the number of on and/or off bursts varies.  A 0 is signified by a rising edge and a 1 by a falling edge with a constant clock period.   So the 2 bit sequence 11 goes on/off on/off  while 10 goes on/off off/on.  Describing 11 requires 4 burst durations, while 10 needs 3 burst durations since off off looks like one longer off duration in Pronto Hex.

However, the total duration of RC5 signals is the same for all commands, assuming that the commands all have the same number of bits.

Edited to fix typos