Is it bad form to use EE models in addons?

Is it OK to use EE model methods in addons or is that considered bad form?

My Health Check accessory caused a bit of trouble for people because I’m using this method to pull a list of available plugins:

$this->EE->addons_model->get_plugins();

That method does an include_once() on each plugin file.

#Line 136 of models/addons_model.php:
@include_once(PATH_PI.$file)

However, the page that displays plugins on the control panel uses another method that also tries to include_once() each plugin file.

#Line 612 of controllers/cp/addons_plugins.php
@include_once($path);

Since the include_once() in my accessory gets called first on every CP page load, the include_once() on the CP’s plugin list page doesn’t include the plugin files (because they’ve already been included) and fails silently.

If I change that second include in addons_plugins.php on line 612 to:

include($path);

I get this fatal error:

Fatal error: Cannot redeclare map_attrs() (previously declared in /www/ypadmin/expressionengine/plugins/pi.magpie.php:1188) in /www/ypadmin/expressionengine/plugins/pi.magpie.php on line 1190

So, it seems the assumption is that the list plugin call will only be made once and not by an addon.

I can certainly walk the plugins directory manually to find plugins, but assumed the existing model method would be the “better” solution.

Am I thinking about this correctly? Or is it better to not touch model methods? Or is it a shortcoming of the plugin implementation?

Appreciate any feedback or ideas.