modx seo vs wordpress seo

Hi,
i come from wordpress and discover modx only a few weeks ago, and as a front end designer i really love it as it really easier to integrate an html template.
I'm often working with a very good seo guy who bring me jobs, i make the design and code , and he make the content and seo.
He really loves wordpress for seo (he had experience with joomla and drupal before, and really prefer wordpress)
so when i talked to him about modx, he was not very enthousiastic, as for him it means learning new technics, and don't know if he will have the same result as in wp
So what can i say to him ?
is there a learning curve also to make a good seo in modx? (another seo friend told me it is very good, but it's not the one who brings me work)
Which are the best tools ? what are the advantages comparing to wp ?
is there a glossary plugin where links appears on the terms of the glossary (he uses that a lot)
If you can help me to convince him it would be great
seo it's really not my job, so i cannot really find everything by myself

SEO is very wide, allot you can do yourself by making clean and logic html/source.
Does he makes landingpages, edits content, urls and headlines etc?
As far as I know in WP you have a Yoast SEO plugin which does allot without doing allot of stuff beside writing your own content.

I dunno if Revolution has any easy SEO plugins.
Maybe: http://modx.com/extras/package/seotab

For Evo I make these tabs myself, add my own canonical url etc etc.

Really depends what he does for SEO in WP.
Writing new content offcourse is pritty easy in Modx.

Thanks,
i don't know what he does exactly, as i'm really not interested in seo, i always delegate this part, i just know he is very good
so i will ask him what he does exactly and perhaps make a new post

MODx is 100% customizable.
If you really know SEO, with modx you can tune any part of your project.

This is the best feature, because each project requires a different approach.

I really don't like how some plugins used on other cms (joomla ,drupal, wp)works.
Seem to be made for those unfamiliar with the seo and prefer to rely on a preset of a plugin.

Thank you, i will tell him