What I was talking about was a holder for another system similar to the Dickensen (I'm sure that I don't have that spelled right) system, but not quite it. The holder, instead of holding the tool shank parallel to a line tangent to the ways on the post holds the shank at about a 30 degree angle to the tangent line. I forget the brand, but I wound up with a holder for that system when I thought that I was bidding on a holder for the Emco-Maier smaller Dickensen. Hmm ... it was probably "Enco" that I confused. Anyway -- I exchanged it for one of the right type that someone else had which did not fit *his* toolpost. :-)
The drill chucks, and the Morse taper holders can be useful when you are doing a lot of on-axis peck drilling when you need to do a lot of pulling the bit back out to clear chips. Use the power feed, disengage the feed, crank back with the carriage handwheel, tap to drop chips, crank back in until the tip contacts, and re-engage the power feed. A *lot* quicker than cranking on the handwheel for the tailstock, but if you have a lever-feed tailstock, or a bed turret, it is not as useful.
Come to think of it -- I also have a three-jaw cut knurling tool on a Morse Taper shank which goes nicely in the Morse taper tool holder. (A lot of things from eBay auctions -- certainly not bought at new prices. :-)
Enjoy, DoN.