a bit late for this decode but someone asked me on my twitter https://twitter.com/CodesUcq to decode Trump's mis-spelling and it turned out to be pretty easy so I'll share it here.
Basically he adds an extra n to dimension.
and so just have to ask ourselves what an "extra n" could mean - and a simple search reveals: Originally a mathematical term, it is used in any conversation on any topic. It is used when referring to something which has been said or done for many more times than one cares to remember.
so yea, it's just Trump saying this has gone on way too many times. I know SB2 had a decode of this that's a bit more elaborate but sometimes occoms razor wins : ) and tho he is a smart cookie he's just like the rest of us - an anon trying to figure this shit out and occasionally gets one wrong.