Here's a frustrating problem I've been having with "assume".
You'll see below that I assume that v'(m) >0 and v''(m) <>
Maple clearly remembers that v'(m) > 0 (as seen in the assumptions list and by looking at the first "is" in (4)), however, it now can't figure out that v'(m) > 0 implies !(v'(m) <>
Strangely, this worked perfectly fine before the additional assumption was added, and looking up the property (6) reveals the correct answer.
Moreover, maple seems to have two sets of assumptions on v'(m) (for six total assumptions, when I would expect four).

Any maple geniuses have an idea as to why Maple's "is" function is confused?

> restart:
_EnvTry := hard;

> assume(D(v)(m) > 0):
getassumptions(v);
is(D(v)(m) <>

> additionally((D@@2)(v)(m) <>
alist := getassumptions(v);

Note how there are suspiciously many assumptions above! I would have expected four.

> is(D(v)(m) > 0);
is(D(v)(m) <>

Not every maple function is confused, this one works fine:

> signum( D(v)(m) );

> about( D(v) );

D(v):
  is used in the following assumed objects
  [D(v)(m)] assumed RealRange(Open(0),infinity)
  [-D(v)(m)] assumed RealRange(-infinity,Open(0))
  [-D(v)(m)] assumed RealRange(-infinity,Open(0))
  [D(v)(m)] assumed RealRange(Open(0),infinity)

> `property/object`[ D(v)(m) ];

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