Must a writer have constant, instant access to her complete vocabulary? Is a nudge or a hint to remind one of the perfect word a sign of weakness? For many, yes.
I used to feel that way, too. Then I learned that Stephen Sondheim uses a thesaurus and a rhyming dictionary. That's Stephen Sondheim, man of the perennially perfect word choice. Now I proudly reach for (or click on) my thesaurus when things get sticky.
The rule for the successful thesaurification of a written passage: If you don't already know the word and its nuances, don't use it just because you found it in a thesaurus. It will never fly. The reference work must only be a reminder of what you already know.
Another option, as illustrated above, is simply to make up the word you need. That's the Dr. Seuss method, so you know it's all right.