Piggyback an extender?

I don't ever recommend daisy chaining extenders. A standard single/dual band extender drops throughput 50% (of what its getting) plus increases latency. When you daisy chain, the 2nd looses another 50% of what its getting so its going to be less than 25% of the router. Plus add in the additional latency. 

You CAN do it provided you go into it with the expectation of what performance penalty and latency penalty you'll take.