biblatex does not print techreport

Question

According to section 2.2 of the BibLaTeX manual, TECHREPORT is a lagacy-supported type. So, why does this example below now print the entry? Is there something more to it? I would rather not use BibLaTeX specific types...

\documentclass{article}

% introduce asticks (*) in list of references with new command mybibitem
%\usepackage{cite}
%\newcommand{\mybibitem}[1]{\stepcounter{enumiv} \bibitem[\textbf{*\arabic{enumiv}}]{#1}}  


% BibLaTeX
\usepackage[
  backend=bibtex,
  style=authoryear,
  firstinits=true,
  maxbibnames=99]{biblatex}
\addbibresource{CV.bib}


\begin{document}

text text text text text text text text text text text text text text text

\nocite{tech2015}

\setlength\bibitemsep{5pt}
\printbibheading[title={Bibliography}]
\printbibliography[type=techreport, heading=subbibliography, title={Reports}]

\end{document}

The .bib file:

@TECHREPORT{tech2015,
  author = {Meyer, B. and Miller, J.},
  title = {{Some Great Report}},
  institution = {The Great Institution},
  year = {2015},
  type = {Total Cool Reports}
}

Answer 1

You can introduce a subtype.

\begin{filecontents}{\jobname.bib}
    @TECHREPORT{MyReport2015,
        author = {Meyer, B. and Miller, J.},
        title = {{Some Great Report}},
        institution = {The Great Institution},
        year = {2015},
        type = {Total Cool Reports},
        entrysubtype={techreport}% <---
    }
\end{filecontents}
\documentclass{article}

\usepackage[
    backend=bibtex,
    style=authoryear,
    firstinits=true,
maxbibnames=99]{biblatex}
\addbibresource{\jobname.bib}


\begin{document}

text text text text text text text text text text
text text text text text

\nocite{*}

\setlength\bibitemsep{5pt}
\printbibheading[title={Bibliography}]
\printbibliography[type=techreport]
other bib:
\printbibliography[subtype=techreport]

\end{document}