Another example where the plotting chart is mandatory would be going from Seattle to Tahiti.
Spook2
At the risk of receiving further derision from the author of this comment, please be accurate on your comments as well as your navigation, it is always possible that someone believes what is written in these posts without bothering to cross refer with source references...
If you are a US registered aircraft, then it is a procedure incorporated in AC91.70A. It is not mandatory, per se, it is an FAA AMOC per the AC, which an operator could meet by a procedure developed by the operator and accepted, not approved by the FAA. It is not and never has been a blanket "Mandatory" requirement to various other non FAA operators. If you are expecting that a plotting chart will protect from GNE's, then the history of FAA registered aircraft lost over NAT airspace where there is a mandatory requirement for such plotting is hardly convincing evidence of efficacy.
On the SA side, no argument, particularly with flex tracks, but that is general information and a plot is not necessarily beneficial, and an ERC gives all the info that is needed, with or without chicken scratches. It is only mandatory when it is mandatory, other times merely operator prudence/risk management per their zen and karma status... The SA side is in relation to other tracks, not your own, I would be amazed if your own navigation confidence is enhanced by what is effectively cave paintings in the age of moving maps & GPS. Having opined that, the navigation problem is hardly great other than in details of accuracy... if you cross the ditch on heading & time, you probably are going to hit land on the other side, not within RMP standards, but the likelihood of a plotting chart saving the day when the data came from a company route or other source other than manual entry (flex track etc) is low. In the case of manual entry, the cross reference of track/dist and total distance is more effective than plotting a possibly incorrect position on a parchment for posterity.
Just curious; how long is it going to take any competent or half way competent crew to reconstruct a position on a Jepp ERC from the flight plan if in the middle of the day (night is easier...) if all INS/GPS fall over? I would think that most crews are aware that they were on/off track ahead/behind FPL WPT time/fuel at any given time in the cruise. From that, the current estimated position is readily obtainable, with/without a prayer wheel/Calc/Ipad/Iphone etc.
A procedure that mitigates risk without unintended consequences may be justifiable. A procedure that exists as a hangover of a bygone era that does not have a practical benefit is of questionable gain. Do your chicken scratches make you feel safer or actually be safer? In your procedures, is the chart cross checked from an independent source of data to ensure that no GNE exists? Cross checking is a fundamental necessity, but does not necessarily require a pictorial representation to be accomplished, indeed the double handling of the chart may increase opportunity for error or complacency, dependent on the practice employed.
(QFA carried plotting charts and plotting tools in a kit, for emergency use, and their implementation was proceduralised with particular failure events. NAT/Polar would be different again).