Does it do any good to keep asking God over and over without thanksgiving?
No, repeatedly asking God without thanksgiving does no good; such asking is not attended to. Prayer and supplication should be made with thanksgiving, thanking Him in advance for what He will do, trusting He answers according to His grace and mercy, not because He is obligated to grant the request.
Les explains that it does not do any good to go before God and ask and ask and ask without thanksgiving; that kind of asking is not paid attention to. Rather, prayer and supplication are to be made with thanksgiving, with the attitude that God does not have to do what is asked. When we ask with thanksgiving, He answers according to His grace and mercy, and we thank Him ahead of time. Les says it took him a long time to learn to thank God first as he prays, thanking Him for what He is going to do with the particular request. Paul refers to the same thing in Thessalonians: make supplications with thanksgiving and let requests be made known to God. God already knows, but He wants communication and wants us to let Him know from the heart what we desire and need.