  We revise the assumptions of the parameters involved in predicting the number
of supernova remnants detectable in the nuclear lines of the decay chain of
44Ti. Specifically, we consider the distribution of the supernova progenitors,
the supernova rate in the Galaxy, the ratios of supernova types, the Galactic
production of 44Ti, and the 44Ti yield from supernovae of different types, to
derive credible bounds on the expected number of detectable remnants. We find
that, within 1 sigma uncertainty, the Galaxy should contain an average of
5.1+2.4-2.0 remnants detectable to a survey with a 44Ti decay line flux limit
of 10E-5 photons/cm2/s, with a probability of detecting a single remnant of
(2.7+10.0-2.4)%, and an expected number of detections between 2 and 9 remnants,
making the single detection of Cas A unlikely but consistent with our models.
Our results show that the probability of detecting the brightest 44Ti flux
source at the high absolute Galactic longitude of Cas A or above is ~10%. Using
the detected flux of Cas A, we attempt to constrain the Galactic supernova rate
and Galactic production of 44Ti, but find the detection to be only weakly
informative. We conclude that even future surveys having 200 times more
sensitivity than state-of-the art surveys can be guaranteed to detect only a
few new remnants, with an expected number of detections between 8 and 21 at a
limiting 44Ti decay flux of 10E-7 photons/cm2/s.
