At some point in your career with SQL Server does parameter sniffing just jump out and attack?

Not quite an answer, but I'll share my experience.

I suspect your problem is caused by out of data statistics. Since you do not have DBA access to the server, I would encourage you to ask the DBA when the last time statistics were updated. This can have a huge impact on performance.

It also sounds like your tables are not indexed very well.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.