Question: As far as I know a pronoun "I" is usually omitted when personal achievements are being described (writing in "First person implied"). For example it's better to write:

> 
> Performed a review of the project's source code. 
> 
> 
> 

than:

> 
> I performed a review of the project's source code. 
> 
> 
> 

But the second statement I want to write is

> 
> For each review issue **I proposed** a way to fix it.
> 
> 
> 

and it just seems to me that omitting "I" here looks a little unusual:

> 
> For each review issue **proposed** a way to fix it.
> 
> 
> 

Am I right? And If I am, then what is the correct, natural way to write that?

Answer: 
This is a [zeugma](https://en.wikipedia.org/wiki/Zeugma_and_syllepsis): "I had" refers to the meaning of "perambulator" as a baby carriage (from which te word "pram" is derived"). "I was" refers to its meaning of "someone who walks".
I'm not sure if it's technically a pun or just some wordplay, but you are definitely interpreting it correctly, yes.