Wav gets its directories from subs in UI, why inherit all that other stuff? It doesn't matter, Wav is fairly simple

Project also inherits from UI, to get these key subs.

Project, in contrast with Wav, needs all those procedures, so that $my_gig->start_transport would be possible.

$paul_brocante->start_transport;

We set $project name for the Once we have set $project_name, everything starts happening.

my $ui = UI::Graphical->new;

my $project = $ui->project(name => "paul_brocante"); my $project = $ui->project(name => "paul_brocante", create => 1); $project->retain("my slider activity"); $project->perform("my slider activity"); $project->start; $project->everything_that_UI_does

consequence: have to rewrite all the UI (especially GUI) procedural code to do $project->start instead of &start, for what? To be able to pass around project objects??

Definitely not necessary.