Can I embed more than one application via div?

According to Book of Vaadin [1]
, when embedding Vaadin application into a web page, I can embed only one application in a page. I have embedded two applications into the page however (two servlets in web.xml and two entries in vaadinConfigurations) and they seem to work fine. Are there any issues with this approach?

[1]

Book of Vaadin - Embedding Applications in Web Pages