From what I've seen enduro's have changed as much as the other disciplines. The Golden age of enduro's was the mid '70's. Enduro's were endurance events; big K's, long days, no rest and to stay on Trail Time was an achievement. No big line up at check points, maybe 2-3 bikes with maybe 2-3 minutes to draw breath, and that was the guns - club level riders rarely arrived before Time and worked their tails off not to 'hour out' - gumbee newcomers were hour out on the first hill or swamp. None of this 30 minutes 'stand around, scratch ya nuts and chat' girlie stuff.
And you didn't get a sighting lap of the special test or the MX
. The course included very technical sections as part of the Trail Timed sections - 1km of swamp, 1km of nasty single wheel track squid line uphill climbs. Arm pump and thigh burn by pm day one and three days to go
. The bikes were heavy, evil and worked hard to kill you. Most bikes were owner modified trail bikes. The gun riders had modified shop or distributor's bikes. Riders had to be good Bush Mechanics as much as riders - or be exceptionally talented and sponsored. Unmodified bikes didn't start and didn't finish (the Japs spoiled that party with reliable enduro bikes like PE's and IT's
). A 'good' course was considered to be a course that gave a balance between very tight technical sections, giving advantage to the 'tiddlers', and high speed sections that gave advantage to the 'big mothers'.
70's enduro's was about endurance and pacing yourself and not bending yourself or the bike in 2-4 days. These days it speed, speed and more speed.
By the early 80's the loss of access to public lands brought down the mileage and concentrated the technical part of the course to private land. These became very technical 'bike breakers' to sort out winners from losers. This period suited the 175-200 class, i.e. KDX200 et al. This changed again with very controlled limited access to public land (very 'loose' trail time to reduce "using the bush as a race track") and winners and losers were sorted at the special tests and MX.
IMHO