Hi Gennady, sorry for very late response.

>>>>> <gennady.uraltsev@gmail.com> writes:

> I illustrate with examples

> Consider the following LaTeX file (attached as main.tex):

> \documentclass{amsart}
> \begin{document}
> \title{Simple AMSart}
> \author{Author McAuthorface}

> \maketitle

> \section{Section \textit{a} : a \LaTeX macro}
> \begin{equation*}
>   \int_{\alpha + \beta = \LaTeX + \dots }
> \end{equation*}
> \end{document}

> 1.	
> *	The macro \textit{a} folds into an "a" as specified by
> TeX-fold-macro-spec-list (value included below) but it gets rendered much
> larger than the surrounding text
> *	I believe because the "enlargement" gets applied twice, but I am not
> sure. 

I tried just enabling TeX-fold-mode without your whole init setting, and
the problem doesn't reproduce with the provided sample latex file.

> 2.	Auctex makes the subscript of the integral in the equation small and
> lowered.

> *	After folding the Greek symbols and the other macros they appear to
> be the same size as "normal" text so they do not inherit the surrounding
> fontification. 

I can observe this behavior. It seems that the attached patch fixes the
problem. Could you test whether it works for you or not?

Regards,
Ikumi Keita