The Reformed understanding of total depravity appears to be wrong. Deuteronomy 30: 11, 14 declares human ability to obey God:
"This commandment that I command you today is not too hard for you, neither is it far off...."The word is very near you. It is in your mouth and in your heart, so that you can do it."
How can you reconcile that passage with your view?
Two related points I wish to highlight here:
1) Isolated, the Deuteronomy verse(s) you cite have every appearance of a Pelagian declaration, but in the context of the whole passage you quoted it quickly becomes evident that the exact opposite is true. Read the entire chapter. What does it say? In the midst of telling them it is not too hard the LORD also provides them with a promise, the very foundation which makes the command not too difficult: "And the LORD your God will circumcise your heart and the heart of your offspring, so that you will love the LORD your God with all your heart and with all your soul, that you may live." (Deuteronomy 30:5-7). Circumcision of heart is another way of expressing regeneration (Col. 2:11). Don't know if you noticed this but the indicative (grace) is the ground for the imperative (commandment) Any obedience they give to God springs from God's prior action of grace in them. The Word is near to them and where you find the Word, the Spirit is also working in the children of promise. The children of promise among the Israelites had been set free and were not only in covenant with God, but given a new heart to understand and obey. The promises of grace, mind you, were just as valid for Old Testament believers as New Testament believers, otherwise, like us, would be stuck in their willful blindness and none of them would have had hope to obey this or any other command of God (Deut 29:4). Human nature has remained constant after the fall. The need for grace does away with any possibility a free will to obey God, for apart from Christ fallen humanity can do nothing.
2) Notice a parallel passage in the New Testament: "God's commands are not too difficult for you, for everyone born of God overcomes the world." (1 John 5:4). Those who are regenerate (born again) have been set free by the Spirit of Christ (John 8:36, Romans 6:18) and God's commands are, therefore, not burdensome or too hard. Read this passage carefully. Being born again is a pre-requisite for the freedom to obey God's commands. Apart from regeneration the commands are too difficult for anyone to obey.
In the New Testament other parallel passages might be found in 1 John 2:29; 3:9; 5:18.
Lastly in light of all this I just wish to ask you a question for you to think about. When you say Deut 30 or any command of God shows human ability are you telling us that such obedience is possible for fallen man apart from grace - apart from any help from the Holy Spirit to do so? As soon as you acknowledge the need for grace is does away with human ability or free will altogether.