I would like to give different equivalent versions of the same theorem, eventually proving the last version. The first time I state the theorem, I would like it to have the number 2.0. Each successive time I revise it, I would like the number to go from 2.n => 2.(n+1). I tried to do this with

```
\newcounter{goalbroad}
\newcounter{goal}
\numberwithin{goal}{goalbroad}
\newtheorem{goal}[goal]{Theorem}

```

and then right before the first

```
\begin{goal}...\end{goal}

```

I call 

```
\setcounter{goalbroad}{\value{thms}}

```

But LaTeX (and LuaLaTex) get stuck there. 

So far, I have only found explanations on restating a theorem with the same numbering. What is going wrong in my approach, and what would be a good way to accomplish this?