Still trying to figure these kind of contracts.
What's the purpose for signing a player to an NHL contract as opposed to an AHL contract?
NHL depth, and to obtain their NHL rights.
Aspirot is can play both sides, isn't a liability defensively, has a bit of a mean streak and seemed to break out offensively last season in Calgary.
Contract has no effect on waivers any more (if it ever did)
One-Way vs Two-Way NHL Contracts and Waivers Breakdown - Beyond the Glass
The main reason is the player can't join the NHL club (and get paid the league minimum) without an NHL contract. The "two-way contract" only means he's paid differently in the NHL and the AHL.
In the old CBA (one of them), there were recall waivers, but like you said the 1way/2way was irrelevant to waivers. Waivers is based on a combination of signing age, current age and games played and has been for as long as I can remember and I started following the business side more closely about 20 years ago after the 04 run and the subsequent lockout and lost season