quoted

Does this also imply that JumboFrames interacts badly with these qdiscs? 
Or IPoIB with its 65000ish byte MTU?

Correct. Of course it is always relative to the link speed. So if your
link is 10x faster and your packets 10x bigger you can get similarly
smooth shaping.

If the later-in-thread mentioned person shaping for their DSL line 
happens to have enabled JumboFrames on their GbE network, will/should 
the qdisc negate that?  Or is the qdisc currently assuming that the 
remote end of the DSL will have asked for a smaller MSS?

rick jones