The post was in response to the many women who have asked him how they could tell whether they were being good Christians in giving of themselves or merely "being a doormat."
Ever helpful, I left a comment referring to Bl. Henry Suso's embrace of a doormat as metaphor for his own spirituality of service. You can be both a good Christian servant and a doormat!
Or, well, maybe you can. At any rate, Bl. Henry could. As a religious mendicant, he was free to think nothing of himself to a degree we'd probably consider irresponsible of someone living in the world. And, as a personally holy man, he wasn't likely to do the wrong thing very often (which isn't to say he was prudent in worldly terms).
Maybe the distinction is between not wanting to be taken advantage of and not wanting to be taken for granted. Being taken advantage of is bad because it implies there are other things you could be doing that will use your time and effort to better advantage. This is the problem Fr. Philip addresses in his post.
Being taken for granted, though, is the expected consequence of being a servant:
Of course, it's not good to take someone else for granted, but correcting that fault in another may not always belong to the one being taken for granted.
Fr. Philip had incidentally mentioned that it is always women who ask about whether they're being taken advantage of. My guess at an explanation, in thirty words or less, is that the greater fear for a woman is to refuse to help when she should, while the greater fear for a man is to be taken advantage of.