Vaesen's EC

But to reassure the reader: the brand of extended cognition my argument relies on is, as will become apparent, quite weak, hence easily digestible. Basically, the only thing one needs to accept is that humans may use cognitive aids to produce cognitive outputs, that we may acquire knowledge by putting to work simple things like glasses, thermometers and computers. Indeed, my argument works whenever one is willing to subscribe to this quite trivial claim. (Vaesen, 2010, p. 3)

Vaesen's version of EC is really as tame as he suggests.  It is consistent with both HEC and HEMC, and, to my knowledge, no one has challenged HEMC. (Although, in a forthcoming paper, Teed Rockwell alleges that there are opponents to HEMC out there.)

Vaesen, K. (2010) "Knowledge without credit, exhibit 4: extended cognition" Synthese online. DOI 10.1007/s11229-010-9744-0