The Keswick Convention didn't start until 1875, long after Methodism started with the Wesleys.
Whether one produced the other is an argument for later but the greater point for me is that about this time a transition in Christian thought and practice was being made that resulted in two extremes that greatly compromised the church of Jesus Christ and weakened it. It was intellectualism on the one hand and emotionalism on the other. Both were Satanic led attacks, that God permitted, and that negatively impacted the Scriptural authority of God's word.
Transition, you ask? God, in his providence is bringing about his design for world history of the nations and the church. This is prophesied to be a renewal, a restitution of all things, a regeneration to his original intent before sin corrupted all things. This includes his creation and his creatures in spite of work arounds that are needed because of wicked and deceived angels and men. There will be no charge against God when this is all over because he has not over ruled the will of men and angels and has permitted all to choose. This is accomplished because I have read the last two chapters in the holy scriptures that tells me this.
The fact that God is providentially in control of his creation and can and does permit transitions throughout history for his own purposes can be demonstrated from the KJV in this passage.
2 Thess 2: Now we beseech you, brethren, by the coming of our Lord Jesus Christ, and by our gathering together unto him,
2 That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand.
3 Let no man deceive you by any means: for that day shall not come, except there come a falling away first, and that man of sin be revealed, the son of perdition;
4 Who opposeth and exalteth himself above all that is called God, or that is worshipped; so that he as God sitteth in the temple of God, shewing himself that he is God.
5 Remember ye not, that, when I was yet with you, I told you these things?
6 And now ye know what withholdeth that he might be revealed in his time.
7 For the mystery of iniquity doth already work: only he who now letteth will let, until he be taken out of the way.
8 And then shall that Wicked be revealed, whom the Lord shall consume with the spirit of his mouth, and shall destroy with the brightness of his coming:
If Paul told them he told us because his words have been preserved. The time table is God's and the Spirit hinders Satan and wicked men from accomplishing their purposes outside that time frame.
9 Even him, whose coming is after the working of Satan with all power and signs and lying wonders,
10 And with all deceivableness of unrighteousness in them that perish; because they received not the love of the truth, that they might be saved.
11 And for this cause God shall send them strong delusion, that they should believe a lie:
12 That they all might be damned who believed not the truth, but had pleasure in unrighteousness.