Short cuts may be accepted by the hardware in procedures, and there may not have been any issues. The key thing to remember is that a short cut may only not have any issues to this point, which does not mean it will not have any in the future. For that matter, the non-shortcut procedure may also have issues down the road. The difference is that one case if following proper procedures any issues are Avayas fault, if not they are your fault.
I upgrade systems from the current release to the next one made available, going through all the releases in between the current installed release, and the final destination release. For the most part that means 3.0 at the earliest to 3.1, to 3.2, not skipping any in between, following each procedure for the next release up from where I am at.
It may take any extra 15 minutes compared to skipping some, but I have never had a DTE cable on an IPO yet. I wonder if that has something to do with it? The downside is, with the hundred or more upgrades I have done, I have gained no experience at connecting via DTE.
When I used to work from home I had three PC's on my network, so I had a machine with each release already installed for upgrading/supporting when I needed to, plus my laptop with 3.2 now. That did save a little time, since I just used a different PC for each upgrade in the proccess.
Eventually I am sure I will get some experience with a DTE cable, but I am willing to wait.