Correct syntax for quotes around embedded variables?

Should embedded variables be surrounded by double quotes?

I am using ee2.10.1. The following code:

{if embed:limit > 0 && embed:paginate <> "yes" }

…fails with this error: Parse error: syntax error, unexpected ‘:’, expecting T_PAAMAYIM_NEKUDOTAYIM in /usr/www/…/Functions.php(688) : eval()’d code on line 241

This works (with or without the parentheses):

{if (embed:limit > 0) && ("{embed:paginate}” <> “yes”) }

But: https://ellislab.com/expressionengine/user-guide/templates/conditionals.html#embedding-tags says that embed variables should not be surrounded by quotes, unless I’m misunderstanding it?

A nitpicking question but I’d be curious to hear what the correct syntax is.

Misha