Is this roundleaf purslane (Portulaca teretifolia)?

I sampled the purslane that grows in my front yard between the sidewalk and the street.

This purslane is a little different than the purslane that I've seen in guides or online photos in that the leaves are more circular. There is some common-looking purslane growing nearby, so I'm unclear on if it's two separate varieties or not.

I've tried it before when it showed up in my yard in past summers. It usually has an interesting flavor, unlike anything else I've tried, and different from other normal purslane. Salty, not tangy. It tends to have a strange aftertaste and if you eat enough of it, it can leave you with a vaguely unpleasant sensation at the back of your throat.

However: this year we both tried the plants growing on this corner.

Observation #1: Eating a few leaves of this at once is not unlike swallowing a mouthful of seawater. It was that salty.

Observation #2: Eating a few leaves left me with a very unpleasant sensation in the back of our throats.

I picked some, washed it twice and sauteed it in olive oil with garlic, but the taste did not improve.

I have sampled the same plant elsewhere in the neighborhood, but never found it to be as salty as the plants in front of my house. I speculate that it has something to do with the toxicity of the soil there, being so close to the road. That corner of the yard is flooded at least twice a year when the storm drains in the neighborhood back up after a downpour, and the ground is steeped in the flotsam and chemicals and oil and god knows what else that comes off the streets.