Definitely, nobody is claiming coax or DC to be a perfect scheme, and in particular Tannoys do not look good in measurements. Fortunately I enjoy music, not measurements!
The Tannoys with a 15" DC (like my Canterbury) are probably pushing that woofer a bit far, asking it to do 1,100 Hz at crossover. They are technically "beaming" at that point but the dispersion of the horn tweeter helps cover for it, somewhat. Within Tannoy fandom you’ll find fans specifically of certain driver sizes, or of the tulip vs. pepperpot wave guides. I love both the 10" and 15", and both in tulip and pepperpot, but they certainly do different things. For some reason I haven’t been enamored by a 12" DC yet; you’d think that would be the good compromise.
As far as Tannoy tulip vs. pepperpot waveguide: pepperpot (usually paired with a single alnico magnet which is VERY expensive) is capable of a more vibrant, lifelike and gorgeous midrange with very fast transients and "startle" factor, but on the flipside its top end can get a bit rough and requires careful system matching to keep this in check! Tulip (dual barium ferrite magnets - this makes the drivers MUCH cheaper) is more even keeled and a great all-around performer, but can’t quite get the midrange exactly as lovely as a good pepperpot.