The DeWalt hammer drill came with an 18 volt
reciprocating saw. It works good on small pieces of lumber, but
disappointed me as a pruning saw.
It's heavy, and it doesn't
take long to deplete the battery when the cutting gets tough.
I would dare say myself armed
with the Felco 600 pruning saw could
outperform someone using the DeWalt 18 volt reciprocating saw with 10
fresh batteries standing by.
I would agree that the very notion of a cordless reciprocating saw is something of a joke to me. The power it takes to overcome that much friction is just impractical. I have heard of it being done, but most miss the mark(hence giving the flops away at the bottom of your cracker jack box).
That said, are you using newish blades? are they made for wood? (not the small teeth close together, but the ripping looking teeth) I seem to remember going through a few blades a day cutting wood with those things.
Maybe it might do better on a pipe where less friction is required.