... And remember, we're talking about recreational diving here, not 6 bottles of hypoxic wreck diving. And ultimately, if a diver can't be bothered to use their computer correctly, maybe they shouldn't be using a computer that gives them the option. Do we remove features that are useful to other divers because a small subset are unable to use it correctly?
The correct use of the Select Gas menu option is solely for switching gas (intra-dive). The number of Rec divers that carry more than one gas in relatively minuscule to those that just carry one gas. Given that, and given OC Rec is for for Rec divers, for
OC Rec, I don't see why the Select Gas menu should be there at all. If you carry more than one gas OC Tec seems like the more appropriate place.
If SW don't remove Select Gas from OC Rec, then I guess they'll find a way to make things work for Rec divers in the Rec areas of the Teric.
On the issue about using Select Gas correctly, the Teric's manual (Rev C) doesn't talk about the behaviour of Select Gas (what it does to the gas switched from). In two parts of the manual (one under Deco Info, the other in OC Tec example IIRC) it talks about not having a gas On that you don't carry. In other parts of the manual (namely the Tec parts) it talks about switching gas. If you approach using the Teric from a Rec perspective, focus on the Rec parts of the manual, chances are when you come to change gas (inter-dive) chances are you'll do it with the first menu option that seems to be correct, it appears to work, and the only way you would know it's incorrect is to then going into Edit Gases and looking. So it's not about being "unable" or "can't be bothered"; it's more about being made aware.
With the changes in FW16, I would expect RevD of the manual to be released at some point and for some explicit comments in the manual about Select Gas assuming it remains.
Or just do what I've done for 5 years now as an NDL Rec diver (no gas switches/deco). I only use the Edit Gases screen and use only 2 gases in the list - top entry for Nitrox and bottom entry for Air.
.
TBH I'm perplexed how I managed to live in bliss of not doing it the right way. OK, so it didn't have any implications (pre FW16) but I'm typically more 'particular' than that
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The other thing I noticed when reading some of the prior posts was terminology.
In SW speak we have:
Active Gas <-- the gas you are breathing at that time. (and only one Gas can be Active at any time).
On or Enabled Gas <-- a gas you intend to use on a dive and it's listed where gases appear (either via Select Gas or Edit Gases).
Off <-- it's listed, not intended for use. It might be carried (emergency gas, a buddy's gas etc - see
@KenGordon post #48 above), although the manual does say it's not carried (6.2.1 Teric).