I would like to wire a double gang box with two pair of receptacles on the same circuit and not switched.

Technique 1: One source told me it is preferable to pigtail hots, neutrals, and grounds to each receptacle in the box so that a possible future receptacle replacement might be easier.

Technique 2: Another technique I have seen is to daisy chain the receptacles using the same wire stripped of some insulation from the middle of the wire to connect to each receptacle post and then to continue those wires to another box. The advantage here I guess is to minimize conductor count in a box.

Which technique is more conventional?

What is the best way to strip insulation off the middle of a wire and what is the recommended spacing of these strippings to accommodate both receptacles?

Thank you.

Pigtailing is the best method, since it relies on the wirenut and twisted wire for a connection, rather than just screw terminals.

When a shared neutral is involved, you must, per code, pigtail the neutral wires, as screw terminals is not allowed because a loose screw terminal will cause an open neutral condition.

Personally I like to daisey chain like you describe, did a quad yesterday, no wirenuts and You have to hook to the screws anyway, and eleminates extra connections.
I take my Kleins(pliers) to expose enough to go around the screw of the first receptacle, about 4 " back from the end of wire. Strip like you would the end of the wire, but only expose enough for the screw, then strip the end. Solid is easier to strip than stranded.
Do not nick the wire.
I also do it as TK mentions, usually if connections have to be made with wirenuts anyway.
Both ways are code and acceptable.

Another thing, if Box fill is a problem, 1 uncut wire is 1 wire, 1 wire and 2 pigtails is 3 wires.
Plus the wirenut is out of the way.

1 uncut wire is 1 wire, 1 wire and 2 pigtails is 3 wires.

Sorry Strat, have to disagree.

“Conductors, no part of which leaves the box, shall not be counted.”