You are right. It is a very time consuming effort to create a clear picture of your ancestral record. As regards the indexes, the name is followed by a number which coincides with a sequential number that appears on the individual document for that year. When these actual indexes are available, your search is enhanced because you can find the record quicker and you have a double check on your translation abilities because they are alphabetical.
Since there is probably not an electronic index yet available (Ancestry and FHS are working on this for the future) physical viewing of these films is the only way to retrieve the record.
I have found that the marriage records give the most complete and accurate info (in total), followed by birth and then death records. The dates will be correct but the names and ages can vary from document to document. This is especially true in areas where illiteracy is quite common.
I have not had the pleasure of finding an index for many years that I have researched, but they are an asset when available. I have not personally discovered any missing names but it sure is possible.
Examining the entire real will also produce info on the mother that is not available in the index.
Try to stay current on Ancestry and Family Search, since they have been uploading many of these records to their sites. It is much easier to do your research from these records than renting films and accommodating the limited hours available at the Family History Center.
Good luck in your pursuit.
Researching surnames Ianniello, Tamburrino, Mattora/Martora/Mattori & Scialla in Santa Maria Capua Vetere, Caserta, Campania.
I'm no pro at this, but I've had quite a bit of luck with the microfilms. But as you said it is very time consuming. What I have been doing is look for the names listed in the margins and then quickly skim each document for names mentioned, and then move on to the next one. I have found that to be a really quick process.
If I find someone that I am looking for,I have been going to the document before and after the one that I am looking act to study the handwriting to figure out the date for the 'numero.'
I used an old machined microfilm machine to do the searches, and then carefully take it off the spools and take it over to a digital machine and then scan the document; and take the reel back to the old school machine.
I have found this to be a really efficient way to go about this.
I have been dealing with records from a small commune that typically have about a decade per record type per year (sometimes more). If I have an idea what I'm looking for; but cannot find it, I go (est. year +5; -5 or sometimes 10), and have had a lot of luck doing it that way.
I have found marriage records to be a real pain, but the information is worth its weight in gold!