Maybe a possible solution to some of the deficiencies in DT would be to create a condensed DT system based on MMA. A good 6 month dose of BJJ/MuayThai/Wrestling/Judo etc. With pressure testing. Without that pressure testing, you're not gaining much.
Thats what DT is....a condensed system of techniques from different arts altered to allow handcuffing.
Its a very condensed basic system....most departments don't have the budget for a 6 month DT training program for all their officers.