You could use the environ package to create a new lvframe environment for frames that will appear in the "long version" of the presentation. The frame environment would be used for those in both. A boolean could then be used to switch between the two:
\documentclass{beamer}
\usepackage{environ}
\newif\iflongversion \longversiontrue%change to \longversiontrue to include the frames in the long version
\NewEnviron{lvframe}[3][]{%
\iflongversion\begin{frame}[environment=lvframe,#1]{#2}{#3}
\BODY
\end{frame}\fi}
\begin{document}
\title{Presentation}
\begin{frame}
\titlepage
\end{frame}
\begin{frame}{Issue 1} % both
\end{frame}
\begin{frame}{Issue 2 - the gist of it} % only short
\end{frame}
\begin{lvframe}{Issue 2 - the detailed version }{} % only long
\end{lvframe}
\begin{lvframe}{Issue 2 - the detailed version, contd.}{} % only long
\end{lvframe}
\begin{frame}{Issue 3} % both
\end{frame}
% etc.
\end{document}
Change \longversionfalse to \longversiontrue to get the "long version".
Edit:
The above is the corrected answer based on the comments from the OP and @MickG below. This definition should handle the most common implementations of \begin{frame}, specifically those of the form \begin{frame}[options]{title}{subtitle}. Note that {} is required if the subtitle argument is not wanted (lvframe does not have the same complex optional argument parsing of frame). Also, this will not work if <overlay> is needed.
multiaudienceas is shown in Hiding some slides in student handouts in Beamer – Ignasi Nov 04 '15 at 08:02