It's a good idea - but I for one am not comfortable with the idea of calling it an obligation on the part of the team. What if Nabokov comes back at age 40, after years of diminishing performances in Russia, and signs for $800k to be somebody's backup? Should St. Louis then be on the hook for him (at vastly reduced ratings) at the $5.5M amount? It seems to me that any remaining contract should represent a team option, and if the team declines to exercise that option the player becomes a UFA.
As noted, we can always drop a European player from our prospect list altogether, so if he is on your list, it means you basically are willing, no,
hoping, he will return so you can honour the remainder of the deal. Once a year, you're given the chance to get out of it (like I will most assuredly do next year, with Nabokov).
Of course, the tough part is the rating he comes back with. Once they are out of the league for a spell, their rating takes a major hit. In the case of Zherdev, it is a hell of a salary to pay (as I recall), for what will most likely be a middling rating. I've already done the same with Emery, who barely had the rating of a 2nd tier back-up upon his return. Then, when he plays his way this year into a better rating for next year, you then have to negotiate a new deal with the Swingsteins.
Good to know not all the misery is mine on this issue in the Central.
