  The MIT and CXC ACIS teams have explored a number of measures to ameliorate
the effects of radiation damage suffered by the ACIS FI CCDs. One of these
measures is a novel CCD read-out method called ``squeegee mode''. A variety of
different implementations of the squeegee mode have now been tested on the I0
CCD.
  Our results for the fitted FWHM at Al-K$\alpha$ and Mn-K$\alpha$ clearly
demonstrate that all the squeegee modes provide improved performance in terms
of reducing CTI and improving spectral resolution. Our analysis of the
detection efficiency shows that the so-called squeegee modes ``Vanilla'' and
``Maximum Observing Efficiency'' provide the same detection efficiency as the
standard clocking, once the decay in the intensity of the radioactive source
has been taken into account. The squeegee modes which utilize the slow parallel
transfer (``Maximum Spectral Resolution'', ``Maximum Angular Resolution'', and
``Sub-Array'') show a significantly lower detection efficiency than the
standard clocking. The slow parallel transfer squeegee modes exhibit severe
grade migration from flight grade 0 to flight grade 64 and a smaller migration
into ASCA g7. The latter effect can explain some of the drop in detection
efficiency. (ABRIDGED ABSTRACT)
