Swiss Flex Pass

If all you have is the Swiss Flexi pass then I think every day you use the pass would count as a flex day. To do what you propose, you would need the Swiss Flexi Pass Combo, which gets you a half-fare card in addition to the flexi pass, that you can use on your "non-flex" days. I think the half fare card is good for 30 days, and there's also a large discount on the price of the half fare card when it's bought with the flexi pass. I believe all this is new in 2015 - in past years, the basic flexi pass worked the way you described. You might want to have a look at the current information about the Swiss rail passes here on the RS site under Travel Tips - Transportation - Train Passes. More detailed information is also on the Swiss tourism website - look under Transportation - Passes.

I read it as Mary does. If you want the half fare on off days, you can add that feature for an additional 60 chf.
http://www.sbb.ch/en/leisure-holidays/holidays--short-breaks-in-switzerland/swisstravelsystem/swiss-travel-pass.html

I do not read it that way. Any Swiss Travel Pass, whether Consecutive or Flexi, offers 50% discounts on lifts (or 25% off the Wengen-Jungfraujoch train) without buying the Half-Fare add-on and without counting a Flexi Pass travel day. That's the way it worked for years before they experimented with automatically adding the Half-Fare Card feature. You would not get half off other train, bus, city tram, or boat transportation, however.

The general rule across Europe (and including when using Eurail-brand multi-country passes in Switzerland) is that a percentage discount does not use a counted flexi pass travel day. Any service that is "covered," including museum admission with Swiss Pass, does start use of a travel day.

Since the Swiss Travel System revamped the program beginning Jan 1, eliminating a lot of features like Twin Passes, you should ask them directly using the contact form: http://www.sbb.ch/en/meta/contact.accitm.fahrplan.html
They should have a definitive answer for you the next day.

I am with Mary and Sam. It seems the validity conditions for the Flexi Pass have changed in 2015, and it no longer provides a 50% discount on "non-covered" days. The Swiss Travel System website says nothing at all about that; instead it says you can add a Half Fare card at half the usual price to get the 50% off benefit that used to be included.

http://www.swisstravelsystem.com/en/passes/swiss-travel-pass-flex.html

I emailed SBB using the link Sam gave and Sam and Mary have it right; Laura does not. You no longer get 50% off lifts on non-covered days with the Flex Pass although it worked that way in the past. Now you need the add-on discounted Half Fare Card and she said that only works between the first and last covered days on the Flex Pass.

Or you can use a covered day on the lifts but that would be a waste. If you are only going to the Berner Oberland you might want a Transfer a Ticket/Half Fare Card combo ( what used to be called the Swiss Card).

Thank you all for the time you've taken to help me with this!!!! I'm sure I'll have other questions as I get further into my planning! Again, thank you.

I also followed up on this and received the same, unfortunate response today, that you now only get lift discounts when you either use a flexi pass travel day or buy the add-on Half-Fare option. (Of course, when using a consecutive pass, all days offer the same coverage.)