I have never had any issues with applying too much Leather Therapy or Leather CPR. I do wipe off the excess after I massage them into the leather because I don't want any residue building up near seams and piping.
The only leather conditioner that I have had to use sparingly has been Black Rocks Leather n Rich. I put it on lightly (one section at a time) rub it in and quickly wipe it off. If you apply BRs too thickly it will get sticky and tacky and take forever to dry.
Of course dark bags (black, navy, mahogany, etc) are more forgiving and it is harder to see flaws after the rehab, but it can be hard to minimize flaws in lighter bags like British Tan. I have seen some bags get splotchy immediately after applying conditioner but it is usually absorbed into the leather after a few days (or a week) and the spottiness disappears. I've had this happen most often with red bags.
But if a light bag has significant flaws and stains then you can make the bag look clean and fresh but you probably won't be able to disguise the flaws as much as desired. In those cases I am usually happy if the Leather Therapy or Black Rocks darkens the leather a little because it may make the flaws less obvious. I once had an issue with a camel bag that I finished with Renapur and I thought that the color looked great but the flaws were more noticeable. I redid the rehab and used Black Rocks to finish the bag and I felt that it worked better in that specific case.
If the bag is spotty because to mold damage then cleaning and conditioning may make the spots more prominent.
The link below shows before and after pics of 5 British Tan bags that I rehabbed and you can see the variations in results. I especially recommend that you look at the 2 tan City Bags in the group. The City Bag that was made in Turkey was in good shape before I started and it rehabbed very well, but the USA bag had significant wear and it didn't turn out as good - but it was improved.
My advice is not to despair too quickly, give the bag some time to absorb the conditioner and some of the splotches may fade; and if you finish the bag with Black Rocks it may help to even out the color. Good luck!
I have been working on rehabbing these tan bags off-and-on for over a month. I cant know what I was thinking when I decided to tackle 5 light-colored bags at one time! But this challenge has finally taught me the secret of successfully rehabbing light-colored bags. Its more "common sense" than...
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