fwiw.....i know fellow builders who are all very talented who use both techniques ....no difference i can discern in the final product.

i glassed the outside of my deck before it was attached. i did not find taping the outside seam and getting a transparent finish particularly difficult at all. the trick for me was to tape it using spare strip of 4mm cloth and not fibreglass tape (which i used for the inside). cloth wets out clearer more easily than tape and was very easy to fare in.

howard