In other threads, I see the mention of regional passes for Switzerland train travel. If we already have a Swiss Pass and are touring around the Bernese Oberland area, do we also need a regional pass? My impression was that the Swiss Pass would cover all the local transportation also. Can anyone advise?
No, the two overlap.
You need to look at the small print on your Swiss pass to see what local transport it covers. A local or regional pass may cover more mountain railways, cable cars or funiculars than a national pass, may cover local buses, and would be cheaper. If you are restricting yourself to a particular area of Switzerland a regional pass can be better value.
But, you have already got a national pass, there is no sense in paying twice.
I think the Swiss Pass is a good deal. Last October, I traveled from Paris to Murren (where my hotel was). I got a inexpensive TGV ticket R/T from Paris to Basel (90 days out) and then used a 4 day Swiss Pass R/T Basel to Interlaken and the pass covered all local trains, buses and cable cars as high as Murren. It was even good on the boats on Thundersee and Brienzersee. I saved 50% on the cable car from Murren to the Schilthorn. I visited Grindelwald and Wengen. The nice thing about traveling from Paris to Basel is that there are more ( and more convenient ) TGV trains to and from Basel then there are from Interlaken. The cost for the 2nd class pass (all you need) was about $240. You could also use it, if you wanted, on a day trip to Bern or Lucerne.
Check the fine print on these, as the deals change from year to year--but we've used the Swiss pass each year, which gives you discount on the mountain stuff (25% on Jungfrau route above Wengen or Kleine S., 50% off Schilthorn trip); I don't think the BO pass gives you any better discount (their website says those routes are discounted, not covered, with the BO pass). I'd say Swiss pass.