The idea that cloaking would confer a great strategic advantage seems quite off base. After all, Romulans can cloak at their leisure, yet they appear to be the definite strategic underdogs, always forced to attempt harebrained schemes to gain the upper hand (and always failing).
In general, giving up technology in an exchange where the opponent gives up aggression or territory is an incredibly advantageous bargain. Technology cannot be monitored, invisibility technology least of all, so you have given up nothing - whereas territory or state of war are obvious things the opponent can do absolutely nothing to obfuscate to his advantage. Basically, the UFP "gave up cloaking" and continued to cloak nevertheless, which must have been a great victory if the Romulans "gave up attacking" or "gave up the Outbackian Sector" and could do absolutely nothing to wiggle out of those quotation marks.
Because the way the romulans were painted, war is inevitable.
And since despite this
there has been no war, the Feds appear to have made a fantastically successful deal here.