In reply to shark:
I've read some unusual comments on this thread.
The current adjectival/tech system is good, gives a lot of information, doesn't need changing.
However. Substituting the sport grade for the current tech grade would give a much more accurate overall grade. Think about it: in what way is swapping the grade of the SINGLE hardest move for that of the WHOLE route going to give you LESS information ? It's nonsense.
Adjectival grading has struggled to clearly indicate danger vs sustained-ness for a long time now (cf was Strawberries graded E5 7a vs E6 6b? ) so now 'E-for-effort' coexists with neckiness. Unfortunately E-for-effort still doesn't give a highly accurate overall grade, though the tech grade does mean we are left knowing something exact about one move on the route. Whoop-ee-doo!
Subsuming effort into an accurate sport grade allows for seriousness to be properly graded - as it now, by the disparity between E and tech/(or sport) grade, but without confusion over how much that E refers to 'effort' - and how much neck you need.
What's difficult to grasp about that?
There is this though: harder trad climbers will be more interested in the sport grade than lower-grade climbers.
They're more likely to be familiar with it, for one thing, but also the lower trad grades are reasonably exact and tend not to cover a huge band of difficulties... Once you get to E5 that starts to really open up into multiple grades and falls apart totally once you get to tech 6c because the system is so compressed ( 6c= anything harder than 6b mostly and so covers many many grades).
E7 6c could be terminal 7b or safe 8a . That needs knowing. Which you would instantly with a sport grade of E7 7b or E7 8a.
What's not to like about that?