For those members not familiar with the drizzle techniques, I'd refer them to:
http://www.astrosurf.com/buil/us/spe9/lrgb22.htm
It is an image processing tool developed to improve some of the undersampled the Hubble images. (Undersampling occurs when the signal data is not sampled by at least two pixels - the Nyquist sampling.)
What Steven has found is that the science data in his spectral images was not enhanced by the drizzle technique.
In spectroscopy we are recommended never to process the raw data beyond the basic needs of darks/ flats/ sky background removal. This ensures the integrity and accuracy of the data. The best solution to improve the data is to collect more! The higher the signal, the higher the signal to noise.
Effective stacking of spectral subs can be done through various freeware processing software - BASS Project, ISIS etc or some astrophotographic programs which have spectroscopy stacking functions - AstroArt6
It's been an interesting investigation, and I thank Steven for his interest and contributions.
Onwards and Upwards