I generally develop a lot with PHP and in the case of where i am generating a grid of check boxes, the PHP generated content removes this problem as it does not insert any spacing/breaks.
Instead of using to remove a CR/LF between elements, I use the SGML processing instruction because minifiers often remove the comments, but not the XML PI. When the PHP PI is processed by PHP, it has the additional benefit of removing the PI completely along with the CR/LF in between, thus saving at least 8 bytes. You can use any arbitrary valid instruction name such as and save two bytes in X(HT)ML.