Don't think so--he mentioned GPS and navigation with-or-without a GPS is a key set of skills for bushwacking.
IMO one should learn and use multiple techniques of navigation to provide cross-checking as one goes and backup in case a particular piece of equipment or technique fails, becomes unusable, or becomes unavailable.
Also many people on this BBS learned and practiced navigation before GPSes became available. Use whatever set of techniques you prefer--it doesn't matter as long as you get were you need to be. Ultimately the GPS is just another tool (as is a map, compass, or altimeter). All are useful, can fail (or be lost), and need to be learned to be used effectively.
Doug